Chapter 5
                             Relationships in Triangles

Tuesday, February 28, 2012
SECTION 5-1
                             Bisectors of Triangles




Tuesday, February 28, 2012
Essential Questions

                 How do you identify and use perpendicular bisectors in
                 triangles?


                 How do you identify and use angle bisectors in
                 triangles?




Tuesday, February 28, 2012
Vocabulary
      1. Perpendicular Bisector:


      2. Concurrent Lines:


      3. Point of Concurrency:


      4. Circumcenter:


      5. Incenter:

Tuesday, February 28, 2012
Vocabulary
      1. Perpendicular Bisector: A segment that not only cuts
          another segment in half, but it also forms a 90° angle at
          the intersection
      2. Concurrent Lines:


      3. Point of Concurrency:


      4. Circumcenter:


      5. Incenter:

Tuesday, February 28, 2012
Vocabulary
      1. Perpendicular Bisector: A segment that not only cuts
          another segment in half, but it also forms a 90° angle at
          the intersection
      2. Concurrent Lines: Three or more lines that intersect at the
          same point
      3. Point of Concurrency:


      4. Circumcenter:


      5. Incenter:

Tuesday, February 28, 2012
Vocabulary
      1. Perpendicular Bisector: A segment that not only cuts
          another segment in half, but it also forms a 90° angle at
          the intersection
      2. Concurrent Lines: Three or more lines that intersect at the
          same point
      3. Point of Concurrency: The common point where three or
          more lines intersect
      4. Circumcenter:


      5. Incenter:

Tuesday, February 28, 2012
Vocabulary
      1. Perpendicular Bisector: A segment that not only cuts
          another segment in half, but it also forms a 90° angle at
          the intersection
      2. Concurrent Lines: Three or more lines that intersect at the
          same point
      3. Point of Concurrency: The common point where three or
          more lines intersect
      4. Circumcenter: The concurrent point where the
         perpendicular bisectors of the sides of a triangle meet
      5. Incenter:

Tuesday, February 28, 2012
Vocabulary
      1. Perpendicular Bisector: A segment that not only cuts
          another segment in half, but it also forms a 90° angle at
          the intersection
      2. Concurrent Lines: Three or more lines that intersect at the
          same point
      3. Point of Concurrency: The common point where three or
          more lines intersect
      4. Circumcenter: The concurrent point where the
         perpendicular bisectors of the sides of a triangle meet
      5. Incenter: The concurrent point where the angle bisectors
          of the angles of a triangle meet
Tuesday, February 28, 2012
5.1 - Perpendicular Bisector
                     Theorem
            If a point lies on the perpendicular bisector of a segment,
             the it is equidistant from the endpoints of the segment




Tuesday, February 28, 2012
5.1 - Perpendicular Bisector
                     Theorem
            If a point lies on the perpendicular bisector of a segment,
             the it is equidistant from the endpoints of the segment




Tuesday, February 28, 2012
5.1 - Perpendicular Bisector
                     Theorem
            If a point lies on the perpendicular bisector of a segment,
             the it is equidistant from the endpoints of the segment




                                           AC = BC




Tuesday, February 28, 2012
5.2 - Converse of the
           Perpendicular Bisector Theorem
            If a point is equidistant from the endpoints of a segment,
              then it is on the perpendicular bisector of the segment




Tuesday, February 28, 2012
5.2 - Converse of the
           Perpendicular Bisector Theorem
            If a point is equidistant from the endpoints of a segment,
              then it is on the perpendicular bisector of the segment




Tuesday, February 28, 2012
5.2 - Converse of the
           Perpendicular Bisector Theorem
            If a point is equidistant from the endpoints of a segment,
              then it is on the perpendicular bisector of the segment




                             If WX = WZ, then XY = ZY



Tuesday, February 28, 2012
5.3 - Circumcenter
                                  Theorem
           The circumcenter (concurrent point where perpendicular
            bisectors intersect) is equidistant from the vertices of a
                                      triangle




Tuesday, February 28, 2012
5.3 - Circumcenter
                                  Theorem
           The circumcenter (concurrent point where perpendicular
            bisectors intersect) is equidistant from the vertices of a
                                      triangle




Tuesday, February 28, 2012
5.3 - Circumcenter
                                  Theorem
           The circumcenter (concurrent point where perpendicular
            bisectors intersect) is equidistant from the vertices of a
                                      triangle


                                      If G is the circumcenter,
                                         then GA = GB = GC




Tuesday, February 28, 2012
5.4 - Angle Bisector
                                   Theorem
                       If a point is on the bisector of an angle, then it is
                             equidistant from the sides of the angle




Tuesday, February 28, 2012
5.4 - Angle Bisector
                                   Theorem
                       If a point is on the bisector of an angle, then it is
                             equidistant from the sides of the angle




Tuesday, February 28, 2012
5.4 - Angle Bisector
                                   Theorem
                       If a point is on the bisector of an angle, then it is
                             equidistant from the sides of the angle



                                             If AD bisects ∠BAC, BD ⊥ AB,
                                              and CD ⊥ AC, then BD = CD




Tuesday, February 28, 2012
5.5 - Converse of the Angle
                 Bisector Theorem
         If a point in the interior of an angle is equidistant from the
           sides of the angle, then it is on the bisector of the angle




Tuesday, February 28, 2012
5.5 - Converse of the Angle
                 Bisector Theorem
         If a point in the interior of an angle is equidistant from the
           sides of the angle, then it is on the bisector of the angle




Tuesday, February 28, 2012
5.5 - Converse of the Angle
                 Bisector Theorem
         If a point in the interior of an angle is equidistant from the
           sides of the angle, then it is on the bisector of the angle



                                 If BD ⊥ AB, CD ⊥ AC, and BD = CD,
                                       then AD bisects ∠BAC




Tuesday, February 28, 2012
5.6 - Incenter Theorem
                 The incenter (concurrent point where angle bisectors
                  meet) is equidistant from each side of the triangle




Tuesday, February 28, 2012
5.6 - Incenter Theorem
                 The incenter (concurrent point where angle bisectors
                  meet) is equidistant from each side of the triangle




Tuesday, February 28, 2012
5.6 - Incenter Theorem
                 The incenter (concurrent point where angle bisectors
                  meet) is equidistant from each side of the triangle



                                       If S is the incenter of ∆MNP,
                                              then RS = TS = US




Tuesday, February 28, 2012
Example 1
                                     Find each measure.

                             a. BC                        b. XY




Tuesday, February 28, 2012
Example 1
                                     Find each measure.

                             a. BC                        b. XY




                        BC = 8.5



Tuesday, February 28, 2012
Example 1
                                     Find each measure.

                             a. BC                        b. XY




                        BC = 8.5                          XY = 6



Tuesday, February 28, 2012
Example 1
                                 Find each measure.

                         c. PQ




Tuesday, February 28, 2012
Example 1
                                 Find each measure.

                         c. PQ

                                    3x + 1 = 5x − 3




Tuesday, February 28, 2012
Example 1
                                 Find each measure.

                         c. PQ

                                    3x + 1 = 5x − 3
                                   -3x      -3x




Tuesday, February 28, 2012
Example 1
                                 Find each measure.

                         c. PQ

                                    3x + 1 = 5x − 3
                                   -3x +3 -3x +3




Tuesday, February 28, 2012
Example 1
                                 Find each measure.

                         c. PQ

                                    3x + 1 = 5x − 3
                                   -3x +3 -3x +3
                                        4 = 2x




Tuesday, February 28, 2012
Example 1
                                 Find each measure.

                         c. PQ

                                    3x + 1 = 5x − 3
                                   -3x +3 -3x +3
                                        4 = 2x
                                         x=2




Tuesday, February 28, 2012
Example 1
                                 Find each measure.

                         c. PQ

                                    3x + 1 = 5x − 3   PQ = 3x + 1
                                   -3x +3 -3x +3
                                        4 = 2x
                                         x=2




Tuesday, February 28, 2012
Example 1
                                 Find each measure.

                         c. PQ

                                    3x + 1 = 5x − 3   PQ = 3x + 1
                                   -3x +3 -3x +3
                                                      PQ = 3(2) + 1
                                        4 = 2x
                                         x=2




Tuesday, February 28, 2012
Example 1
                                 Find each measure.

                         c. PQ

                                    3x + 1 = 5x − 3   PQ = 3x + 1
                                   -3x +3 -3x +3
                                                      PQ = 3(2) + 1
                                        4 = 2x
                                                       PQ = 6 + 1
                                         x=2




Tuesday, February 28, 2012
Example 1
                                 Find each measure.

                         c. PQ

                                    3x + 1 = 5x − 3   PQ = 3x + 1
                                   -3x +3 -3x +3
                                                      PQ = 3(2) + 1
                                        4 = 2x
                                                       PQ = 6 + 1
                                         x=2
                                                         PQ = 7




Tuesday, February 28, 2012
Example 2
              A triangular shaped garden is shown. Can a fountain be
               placed at the circumcenter and still be in the garden?




Tuesday, February 28, 2012
Example 2
              A triangular shaped garden is shown. Can a fountain be
               placed at the circumcenter and still be in the garden?




Tuesday, February 28, 2012
Example 2
              A triangular shaped garden is shown. Can a fountain be
               placed at the circumcenter and still be in the garden?




                                                        No, it cannot




Tuesday, February 28, 2012
Question
     If you have an obtuse triangle, where will the circumcenter be?



      If you have an acute triangle, where will the circumcenter be?



       If you have an right triangle, where will the circumcenter be?




Tuesday, February 28, 2012
Question
     If you have an obtuse triangle, where will the circumcenter be?

                             It will be outside the triangle

      If you have an acute triangle, where will the circumcenter be?



       If you have an right triangle, where will the circumcenter be?




Tuesday, February 28, 2012
Question
     If you have an obtuse triangle, where will the circumcenter be?

                             It will be outside the triangle

      If you have an acute triangle, where will the circumcenter be?

                             It will be inside the triangle

       If you have an right triangle, where will the circumcenter be?




Tuesday, February 28, 2012
Question
     If you have an obtuse triangle, where will the circumcenter be?

                                    It will be outside the triangle

      If you have an acute triangle, where will the circumcenter be?

                                    It will be inside the triangle

       If you have an right triangle, where will the circumcenter be?

                             It will be on the hypotenuse of the triangle


Tuesday, February 28, 2012
Example 3
                                     Find each measure.

                             a. DB                        b. m∠WYZ

                                                              m∠WYX = 28°




Tuesday, February 28, 2012
Example 3
                                      Find each measure.

                             a. DB                         b. m∠WYZ

                                                               m∠WYX = 28°




                             DB = 5



Tuesday, February 28, 2012
Example 3
                                      Find each measure.

                             a. DB                         b. m∠WYZ

                                                               m∠WYX = 28°




                             DB = 5                    m∠WYZ = 28°



Tuesday, February 28, 2012
Example 3
                                 Find each measure.

                         c. QS




Tuesday, February 28, 2012
Example 3
                                 Find each measure.

                         c. QS

                                    4x - 1 = 3x + 2




Tuesday, February 28, 2012
Example 3
                                 Find each measure.

                         c. QS

                                    4x - 1 = 3x + 2
                                   -3x      -3x




Tuesday, February 28, 2012
Example 3
                                 Find each measure.

                         c. QS

                                    4x - 1 = 3x + 2
                                   -3x +1 -3x +1




Tuesday, February 28, 2012
Example 3
                                 Find each measure.

                         c. QS

                                    4x - 1 = 3x + 2
                                   -3x +1 -3x +1
                                        x=3




Tuesday, February 28, 2012
Example 3
                                 Find each measure.

                         c. QS

                                    4x - 1 = 3x + 2   QS = 4x - 1
                                   -3x +1 -3x +1
                                        x=3




Tuesday, February 28, 2012
Example 3
                                 Find each measure.

                         c. QS

                                    4x - 1 = 3x + 2   QS = 4x - 1
                                   -3x +1 -3x +1
                                                      QS = 4(3) - 1
                                        x=3




Tuesday, February 28, 2012
Example 3
                                 Find each measure.

                         c. QS

                                    4x - 1 = 3x + 2   QS = 4x - 1
                                   -3x +1 -3x +1
                                                      QS = 4(3) - 1
                                        x=3
                                                       QS = 12 - 1




Tuesday, February 28, 2012
Example 3
                                 Find each measure.

                         c. QS

                                    4x - 1 = 3x + 2   QS = 4x - 1
                                   -3x +1 -3x +1
                                                      QS = 4(3) - 1
                                        x=3
                                                       QS = 12 - 1
                                                        QS = 11




Tuesday, February 28, 2012
Example 4
                       Find each measure if S is the incenter of ∆MNP.
               a. SU




Tuesday, February 28, 2012
Example 4
                       Find each measure if S is the incenter of ∆MNP.
               a. SU
                                           SU is a leg in a right triangle




Tuesday, February 28, 2012
Example 4
                       Find each measure if S is the incenter of ∆MNP.
               a. SU
                                           SU is a leg in a right triangle
                                                    a +b =c
                                                     2    2    2




Tuesday, February 28, 2012
Example 4
                       Find each measure if S is the incenter of ∆MNP.
               a. SU
                                           SU is a leg in a right triangle
                                                   a +b =c
                                                     2    2    2


                                                   a + 8 = 10
                                                    2   2    2




Tuesday, February 28, 2012
Example 4
                       Find each measure if S is the incenter of ∆MNP.
               a. SU
                                           SU is a leg in a right triangle
                                                    a +b =c
                                                     2    2    2


                                                    a + 8 = 10
                                                      2  2    2


                                                   a + 64 = 100
                                                     2




Tuesday, February 28, 2012
Example 4
                       Find each measure if S is the incenter of ∆MNP.
               a. SU
                                           SU is a leg in a right triangle
                                                    a +b =c
                                                     2    2    2


                                                    a + 8 = 10
                                                      2    2   2


                                                   a + 64 = 100
                                                     2


                                                        a = 36
                                                         2




Tuesday, February 28, 2012
Example 4
                       Find each measure if S is the incenter of ∆MNP.
               a. SU
                                           SU is a leg in a right triangle
                                                    a +b =c
                                                     2    2    2


                                                    a + 8 = 10
                                                      2    2   2


                                                   a + 64 = 100
                                                     2


                                                        a = 36
                                                         2

                                                         a=6




Tuesday, February 28, 2012
Example 4
                       Find each measure if S is the incenter of ∆MNP.
               a. SU
                                           SU is a leg in a right triangle
                                                    a +b =c
                                                     2      2     2


                                                    a + 8 = 10
                                                      2    2   2


                                                   a + 64 = 100
                                                     2


                                                        a = 36
                                                         2

                                                         a=6
                                                         SU = 6


Tuesday, February 28, 2012
Example 4
                       Find each measure if S is the incenter of ∆MNP.

               b. m∠SPU




Tuesday, February 28, 2012
Example 4
                       Find each measure if S is the incenter of ∆MNP.

               b. m∠SPU              An incenter is created at the concurrent
                                           point of the angle bisectors




Tuesday, February 28, 2012
Example 4
                       Find each measure if S is the incenter of ∆MNP.

               b. m∠SPU              An incenter is created at the concurrent
                                           point of the angle bisectors
                                            m∠MNP = 28 + 28 = 56°




Tuesday, February 28, 2012
Example 4
                       Find each measure if S is the incenter of ∆MNP.

               b. m∠SPU              An incenter is created at the concurrent
                                           point of the angle bisectors
                                            m∠MNP = 28 + 28 = 56°
                                            m∠NMP = 31 + 31 = 62°




Tuesday, February 28, 2012
Example 4
                       Find each measure if S is the incenter of ∆MNP.

               b. m∠SPU              An incenter is created at the concurrent
                                           point of the angle bisectors
                                            m∠MNP = 28 + 28 = 56°
                                            m∠NMP = 31 + 31 = 62°
                                            m∠MPN = 180 − 62 − 56 = 62°




Tuesday, February 28, 2012
Example 4
                       Find each measure if S is the incenter of ∆MNP.

               b. m∠SPU              An incenter is created at the concurrent
                                           point of the angle bisectors
                                            m∠MNP = 28 + 28 = 56°
                                            m∠NMP = 31 + 31 = 62°
                                            m∠MPN = 180 − 62 − 56 = 62°
                                                   1
                                            m∠SPU = (62) = 31°
                                                   2

Tuesday, February 28, 2012
Example 4
                       Find each measure if S is the incenter of ∆MNP.

               b. m∠SPU                An incenter is created at the concurrent
                                             point of the angle bisectors
                                               m∠MNP = 28 + 28 = 56°
                                              m∠NMP = 31 + 31 = 62°
                                              m∠MPN = 180 − 62 − 56 = 62°
                                                     1
                                              m∠SPU = (62) = 31°
                                                     2
                             Check: 28 + 28 + 31 + 31 + 31 + 31 = 180
Tuesday, February 28, 2012
Check Your Understading


                             Make sure to review p. 327 #1-8




Tuesday, February 28, 2012
Problem Set




Tuesday, February 28, 2012
Problem Set


                                p. 327 #9-29 odd, 48




                "Great opportunities to help others seldom come, but
                  small ones surround us every day." - Sally Koch
Tuesday, February 28, 2012

Geometry Section 5-1 1112

  • 1.
    Chapter 5 Relationships in Triangles Tuesday, February 28, 2012
  • 2.
    SECTION 5-1 Bisectors of Triangles Tuesday, February 28, 2012
  • 3.
    Essential Questions How do you identify and use perpendicular bisectors in triangles? How do you identify and use angle bisectors in triangles? Tuesday, February 28, 2012
  • 4.
    Vocabulary 1. Perpendicular Bisector: 2. Concurrent Lines: 3. Point of Concurrency: 4. Circumcenter: 5. Incenter: Tuesday, February 28, 2012
  • 5.
    Vocabulary 1. Perpendicular Bisector: A segment that not only cuts another segment in half, but it also forms a 90° angle at the intersection 2. Concurrent Lines: 3. Point of Concurrency: 4. Circumcenter: 5. Incenter: Tuesday, February 28, 2012
  • 6.
    Vocabulary 1. Perpendicular Bisector: A segment that not only cuts another segment in half, but it also forms a 90° angle at the intersection 2. Concurrent Lines: Three or more lines that intersect at the same point 3. Point of Concurrency: 4. Circumcenter: 5. Incenter: Tuesday, February 28, 2012
  • 7.
    Vocabulary 1. Perpendicular Bisector: A segment that not only cuts another segment in half, but it also forms a 90° angle at the intersection 2. Concurrent Lines: Three or more lines that intersect at the same point 3. Point of Concurrency: The common point where three or more lines intersect 4. Circumcenter: 5. Incenter: Tuesday, February 28, 2012
  • 8.
    Vocabulary 1. Perpendicular Bisector: A segment that not only cuts another segment in half, but it also forms a 90° angle at the intersection 2. Concurrent Lines: Three or more lines that intersect at the same point 3. Point of Concurrency: The common point where three or more lines intersect 4. Circumcenter: The concurrent point where the perpendicular bisectors of the sides of a triangle meet 5. Incenter: Tuesday, February 28, 2012
  • 9.
    Vocabulary 1. Perpendicular Bisector: A segment that not only cuts another segment in half, but it also forms a 90° angle at the intersection 2. Concurrent Lines: Three or more lines that intersect at the same point 3. Point of Concurrency: The common point where three or more lines intersect 4. Circumcenter: The concurrent point where the perpendicular bisectors of the sides of a triangle meet 5. Incenter: The concurrent point where the angle bisectors of the angles of a triangle meet Tuesday, February 28, 2012
  • 10.
    5.1 - PerpendicularBisector Theorem If a point lies on the perpendicular bisector of a segment, the it is equidistant from the endpoints of the segment Tuesday, February 28, 2012
  • 11.
    5.1 - PerpendicularBisector Theorem If a point lies on the perpendicular bisector of a segment, the it is equidistant from the endpoints of the segment Tuesday, February 28, 2012
  • 12.
    5.1 - PerpendicularBisector Theorem If a point lies on the perpendicular bisector of a segment, the it is equidistant from the endpoints of the segment AC = BC Tuesday, February 28, 2012
  • 13.
    5.2 - Converseof the Perpendicular Bisector Theorem If a point is equidistant from the endpoints of a segment, then it is on the perpendicular bisector of the segment Tuesday, February 28, 2012
  • 14.
    5.2 - Converseof the Perpendicular Bisector Theorem If a point is equidistant from the endpoints of a segment, then it is on the perpendicular bisector of the segment Tuesday, February 28, 2012
  • 15.
    5.2 - Converseof the Perpendicular Bisector Theorem If a point is equidistant from the endpoints of a segment, then it is on the perpendicular bisector of the segment If WX = WZ, then XY = ZY Tuesday, February 28, 2012
  • 16.
    5.3 - Circumcenter Theorem The circumcenter (concurrent point where perpendicular bisectors intersect) is equidistant from the vertices of a triangle Tuesday, February 28, 2012
  • 17.
    5.3 - Circumcenter Theorem The circumcenter (concurrent point where perpendicular bisectors intersect) is equidistant from the vertices of a triangle Tuesday, February 28, 2012
  • 18.
    5.3 - Circumcenter Theorem The circumcenter (concurrent point where perpendicular bisectors intersect) is equidistant from the vertices of a triangle If G is the circumcenter, then GA = GB = GC Tuesday, February 28, 2012
  • 19.
    5.4 - AngleBisector Theorem If a point is on the bisector of an angle, then it is equidistant from the sides of the angle Tuesday, February 28, 2012
  • 20.
    5.4 - AngleBisector Theorem If a point is on the bisector of an angle, then it is equidistant from the sides of the angle Tuesday, February 28, 2012
  • 21.
    5.4 - AngleBisector Theorem If a point is on the bisector of an angle, then it is equidistant from the sides of the angle If AD bisects ∠BAC, BD ⊥ AB, and CD ⊥ AC, then BD = CD Tuesday, February 28, 2012
  • 22.
    5.5 - Converseof the Angle Bisector Theorem If a point in the interior of an angle is equidistant from the sides of the angle, then it is on the bisector of the angle Tuesday, February 28, 2012
  • 23.
    5.5 - Converseof the Angle Bisector Theorem If a point in the interior of an angle is equidistant from the sides of the angle, then it is on the bisector of the angle Tuesday, February 28, 2012
  • 24.
    5.5 - Converseof the Angle Bisector Theorem If a point in the interior of an angle is equidistant from the sides of the angle, then it is on the bisector of the angle If BD ⊥ AB, CD ⊥ AC, and BD = CD, then AD bisects ∠BAC Tuesday, February 28, 2012
  • 25.
    5.6 - IncenterTheorem The incenter (concurrent point where angle bisectors meet) is equidistant from each side of the triangle Tuesday, February 28, 2012
  • 26.
    5.6 - IncenterTheorem The incenter (concurrent point where angle bisectors meet) is equidistant from each side of the triangle Tuesday, February 28, 2012
  • 27.
    5.6 - IncenterTheorem The incenter (concurrent point where angle bisectors meet) is equidistant from each side of the triangle If S is the incenter of ∆MNP, then RS = TS = US Tuesday, February 28, 2012
  • 28.
    Example 1 Find each measure. a. BC b. XY Tuesday, February 28, 2012
  • 29.
    Example 1 Find each measure. a. BC b. XY BC = 8.5 Tuesday, February 28, 2012
  • 30.
    Example 1 Find each measure. a. BC b. XY BC = 8.5 XY = 6 Tuesday, February 28, 2012
  • 31.
    Example 1 Find each measure. c. PQ Tuesday, February 28, 2012
  • 32.
    Example 1 Find each measure. c. PQ 3x + 1 = 5x − 3 Tuesday, February 28, 2012
  • 33.
    Example 1 Find each measure. c. PQ 3x + 1 = 5x − 3 -3x -3x Tuesday, February 28, 2012
  • 34.
    Example 1 Find each measure. c. PQ 3x + 1 = 5x − 3 -3x +3 -3x +3 Tuesday, February 28, 2012
  • 35.
    Example 1 Find each measure. c. PQ 3x + 1 = 5x − 3 -3x +3 -3x +3 4 = 2x Tuesday, February 28, 2012
  • 36.
    Example 1 Find each measure. c. PQ 3x + 1 = 5x − 3 -3x +3 -3x +3 4 = 2x x=2 Tuesday, February 28, 2012
  • 37.
    Example 1 Find each measure. c. PQ 3x + 1 = 5x − 3 PQ = 3x + 1 -3x +3 -3x +3 4 = 2x x=2 Tuesday, February 28, 2012
  • 38.
    Example 1 Find each measure. c. PQ 3x + 1 = 5x − 3 PQ = 3x + 1 -3x +3 -3x +3 PQ = 3(2) + 1 4 = 2x x=2 Tuesday, February 28, 2012
  • 39.
    Example 1 Find each measure. c. PQ 3x + 1 = 5x − 3 PQ = 3x + 1 -3x +3 -3x +3 PQ = 3(2) + 1 4 = 2x PQ = 6 + 1 x=2 Tuesday, February 28, 2012
  • 40.
    Example 1 Find each measure. c. PQ 3x + 1 = 5x − 3 PQ = 3x + 1 -3x +3 -3x +3 PQ = 3(2) + 1 4 = 2x PQ = 6 + 1 x=2 PQ = 7 Tuesday, February 28, 2012
  • 41.
    Example 2 A triangular shaped garden is shown. Can a fountain be placed at the circumcenter and still be in the garden? Tuesday, February 28, 2012
  • 42.
    Example 2 A triangular shaped garden is shown. Can a fountain be placed at the circumcenter and still be in the garden? Tuesday, February 28, 2012
  • 43.
    Example 2 A triangular shaped garden is shown. Can a fountain be placed at the circumcenter and still be in the garden? No, it cannot Tuesday, February 28, 2012
  • 44.
    Question If you have an obtuse triangle, where will the circumcenter be? If you have an acute triangle, where will the circumcenter be? If you have an right triangle, where will the circumcenter be? Tuesday, February 28, 2012
  • 45.
    Question If you have an obtuse triangle, where will the circumcenter be? It will be outside the triangle If you have an acute triangle, where will the circumcenter be? If you have an right triangle, where will the circumcenter be? Tuesday, February 28, 2012
  • 46.
    Question If you have an obtuse triangle, where will the circumcenter be? It will be outside the triangle If you have an acute triangle, where will the circumcenter be? It will be inside the triangle If you have an right triangle, where will the circumcenter be? Tuesday, February 28, 2012
  • 47.
    Question If you have an obtuse triangle, where will the circumcenter be? It will be outside the triangle If you have an acute triangle, where will the circumcenter be? It will be inside the triangle If you have an right triangle, where will the circumcenter be? It will be on the hypotenuse of the triangle Tuesday, February 28, 2012
  • 48.
    Example 3 Find each measure. a. DB b. m∠WYZ m∠WYX = 28° Tuesday, February 28, 2012
  • 49.
    Example 3 Find each measure. a. DB b. m∠WYZ m∠WYX = 28° DB = 5 Tuesday, February 28, 2012
  • 50.
    Example 3 Find each measure. a. DB b. m∠WYZ m∠WYX = 28° DB = 5 m∠WYZ = 28° Tuesday, February 28, 2012
  • 51.
    Example 3 Find each measure. c. QS Tuesday, February 28, 2012
  • 52.
    Example 3 Find each measure. c. QS 4x - 1 = 3x + 2 Tuesday, February 28, 2012
  • 53.
    Example 3 Find each measure. c. QS 4x - 1 = 3x + 2 -3x -3x Tuesday, February 28, 2012
  • 54.
    Example 3 Find each measure. c. QS 4x - 1 = 3x + 2 -3x +1 -3x +1 Tuesday, February 28, 2012
  • 55.
    Example 3 Find each measure. c. QS 4x - 1 = 3x + 2 -3x +1 -3x +1 x=3 Tuesday, February 28, 2012
  • 56.
    Example 3 Find each measure. c. QS 4x - 1 = 3x + 2 QS = 4x - 1 -3x +1 -3x +1 x=3 Tuesday, February 28, 2012
  • 57.
    Example 3 Find each measure. c. QS 4x - 1 = 3x + 2 QS = 4x - 1 -3x +1 -3x +1 QS = 4(3) - 1 x=3 Tuesday, February 28, 2012
  • 58.
    Example 3 Find each measure. c. QS 4x - 1 = 3x + 2 QS = 4x - 1 -3x +1 -3x +1 QS = 4(3) - 1 x=3 QS = 12 - 1 Tuesday, February 28, 2012
  • 59.
    Example 3 Find each measure. c. QS 4x - 1 = 3x + 2 QS = 4x - 1 -3x +1 -3x +1 QS = 4(3) - 1 x=3 QS = 12 - 1 QS = 11 Tuesday, February 28, 2012
  • 60.
    Example 4 Find each measure if S is the incenter of ∆MNP. a. SU Tuesday, February 28, 2012
  • 61.
    Example 4 Find each measure if S is the incenter of ∆MNP. a. SU SU is a leg in a right triangle Tuesday, February 28, 2012
  • 62.
    Example 4 Find each measure if S is the incenter of ∆MNP. a. SU SU is a leg in a right triangle a +b =c 2 2 2 Tuesday, February 28, 2012
  • 63.
    Example 4 Find each measure if S is the incenter of ∆MNP. a. SU SU is a leg in a right triangle a +b =c 2 2 2 a + 8 = 10 2 2 2 Tuesday, February 28, 2012
  • 64.
    Example 4 Find each measure if S is the incenter of ∆MNP. a. SU SU is a leg in a right triangle a +b =c 2 2 2 a + 8 = 10 2 2 2 a + 64 = 100 2 Tuesday, February 28, 2012
  • 65.
    Example 4 Find each measure if S is the incenter of ∆MNP. a. SU SU is a leg in a right triangle a +b =c 2 2 2 a + 8 = 10 2 2 2 a + 64 = 100 2 a = 36 2 Tuesday, February 28, 2012
  • 66.
    Example 4 Find each measure if S is the incenter of ∆MNP. a. SU SU is a leg in a right triangle a +b =c 2 2 2 a + 8 = 10 2 2 2 a + 64 = 100 2 a = 36 2 a=6 Tuesday, February 28, 2012
  • 67.
    Example 4 Find each measure if S is the incenter of ∆MNP. a. SU SU is a leg in a right triangle a +b =c 2 2 2 a + 8 = 10 2 2 2 a + 64 = 100 2 a = 36 2 a=6 SU = 6 Tuesday, February 28, 2012
  • 68.
    Example 4 Find each measure if S is the incenter of ∆MNP. b. m∠SPU Tuesday, February 28, 2012
  • 69.
    Example 4 Find each measure if S is the incenter of ∆MNP. b. m∠SPU An incenter is created at the concurrent point of the angle bisectors Tuesday, February 28, 2012
  • 70.
    Example 4 Find each measure if S is the incenter of ∆MNP. b. m∠SPU An incenter is created at the concurrent point of the angle bisectors m∠MNP = 28 + 28 = 56° Tuesday, February 28, 2012
  • 71.
    Example 4 Find each measure if S is the incenter of ∆MNP. b. m∠SPU An incenter is created at the concurrent point of the angle bisectors m∠MNP = 28 + 28 = 56° m∠NMP = 31 + 31 = 62° Tuesday, February 28, 2012
  • 72.
    Example 4 Find each measure if S is the incenter of ∆MNP. b. m∠SPU An incenter is created at the concurrent point of the angle bisectors m∠MNP = 28 + 28 = 56° m∠NMP = 31 + 31 = 62° m∠MPN = 180 − 62 − 56 = 62° Tuesday, February 28, 2012
  • 73.
    Example 4 Find each measure if S is the incenter of ∆MNP. b. m∠SPU An incenter is created at the concurrent point of the angle bisectors m∠MNP = 28 + 28 = 56° m∠NMP = 31 + 31 = 62° m∠MPN = 180 − 62 − 56 = 62° 1 m∠SPU = (62) = 31° 2 Tuesday, February 28, 2012
  • 74.
    Example 4 Find each measure if S is the incenter of ∆MNP. b. m∠SPU An incenter is created at the concurrent point of the angle bisectors m∠MNP = 28 + 28 = 56° m∠NMP = 31 + 31 = 62° m∠MPN = 180 − 62 − 56 = 62° 1 m∠SPU = (62) = 31° 2 Check: 28 + 28 + 31 + 31 + 31 + 31 = 180 Tuesday, February 28, 2012
  • 75.
    Check Your Understading Make sure to review p. 327 #1-8 Tuesday, February 28, 2012
  • 76.
  • 77.
    Problem Set p. 327 #9-29 odd, 48 "Great opportunities to help others seldom come, but small ones surround us every day." - Sally Koch Tuesday, February 28, 2012