Slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. If you continue browsing the site, you agree to the use of cookies on this website. See our User Agreement and Privacy Policy.

Slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. If you continue browsing the site, you agree to the use of cookies on this website. See our Privacy Policy and User Agreement for details.

Like this presentation? Why not share!

1,970 views

1,565 views

1,565 views

Published on

No Downloads

Total views

1,970

On SlideShare

0

From Embeds

0

Number of Embeds

0

Shares

0

Downloads

46

Comments

0

Likes

1

No embeds

No notes for slide

- 1. Triangles and Angles
- 2. Triangles Triangle – 3 segments joining 3 non-collinear points, called vertices.
- 3. Classification By Sides Classification By Angles
- 4. Classifying Triangles • In classifying triangles, be as specific as possible. Acute, Scalene Obtuse, Isosceles
- 5. Theorem 4.1 – Triangle Sum Theorem • The sum of the measures of the interior angles of a triangle is 180o . m A + m∠ B + m C = 180∠ ∠ o
- 6. To Prove Given: ΔABC Prove: m 1 + m 2 + m 3 = 180∠ ∠ ∠ o Parallel Postulate 2. m 4 + m∠ 2 + m 5 = 180∠ ∠ o Angle addition postulate, def’n of a straight angle 3. 1 4, 3 5∠ ≅ ∠ ∠ ≅ ∠ Alternate interior angles theorem 4. m 1 = m 4, m 3 = m 5∠ ∠ ∠ ∠ Definition of congruent angles 5. m 1 + m 2 + m 3 = 180∠ ∠ ∠ o Substitution property of equality
- 7. Corollary to Triangle Sum Theorem • A corollary is a statement that readily follows from a theorem. The acute angles of a right triangle are complementary. m A + m∠ B = 90∠ o
- 8. Example 1 Find the value of x in the diagram.
- 9. Theorem 4.2- Exterior Angles Theorem • The measure of an exterior angle is equal to the sum of the measures of the 2 non-adjacent interior angles. m 1 = m∠ A + m B∠ ∠
- 10. Example 2 Solve for y in the diagram.
- 11. Checkpoint: Complete the exercises.
- 12. Homework • Exercise 4.1 page 198: 1-47, odd.

No public clipboards found for this slide

×
### Save the most important slides with Clipping

Clipping is a handy way to collect and organize the most important slides from a presentation. You can keep your great finds in clipboards organized around topics.

Be the first to comment