1) The document discusses measuring segments and angles on a number line including finding the length, midpoint, and using the segment addition postulate. 2) It provides examples of finding the length of segments using coordinates and the segment addition postulate to solve for unknown values. 3) The final example shows using the definition of midpoint and the segment addition postulate to write and solve an equation to find the midpoint and lengths of segments of a triangle.

1. 1.5: Measuring Segments and AnglesPrentice Hall Geometry

2. CEABD0-88-2-4-1246-6The numerical location of a point on a number line.Coordinate :On a number line length AB = AB = |B - A|Length :On a number line, midpoint of AB = 1/2 (B+A) Midpoint :

3. Find which two of the segments XY, ZY, and ZW are congruent. Because XY = ZW, XYZW.Measuring Segments and AnglesGEOMETRY LESSON 1-4Find the length of each segment.XY = | –5 – (–1)| = | –4| = 4ZY = | 2 – (–1)| = |3| = 3ZW = | 2 – 6| = |–4| = 4

4. The Segment Addition PostulateIf three points A, B, and C are collinear and B is between A and C, then AB + BC = AC.ABC

5. AN = 2x – 6 = 2(8) – 6 = 10NB = x + 7 = (8) + 7 = 15Substitute 8 for x.If AB = 25, find the value of x. Then find AN and NB.Use the Segment Addition Postulate to write an equation.AN + NB = ABSegment Addition Postulate(2x – 6) + (x + 7) = 25 Substitute.3x + 1 = 25 Simplify the left side. 3x = 24 Subtract 1 from each side.x = 8 Divide each side by 3.AN = 10 and NB = 15, which checks because the sum of the segment lengths equals 25.

6. RM = 5x + 9 = 5(15) + 9 = 84 MT = 8x – 36 = 8(15) – 36 = 84Substitute 15 for x.RM and MT are each 84, which is half of 168, the length of RT.Mis the midpoint of RT. Find RM, MT, and RT.Use the definition of midpoint to write an equation.RM = MTDefinition of midpoint5x + 9 = 8x – 36Substitute.5x + 45 = 8xAdd 36 to each side. 45 = 3xSubtract 5x from each side. 15 = xDivide each side by 3.RT = RM + MT= 168

7. Homework: P. 33 (2-14EVENS, 29-37, 39-43, 45-52 WRITE OUT SENTENCESQuiz tomorrow!!