1. Name the type of triangle shown below.
11/17/09 Do Now
Name the type of triangle shown below.
135°

2. 4-2 Angle Measures in Triangles
Objective: Calculate angle measures in triangles using triangle sum theorem, and exterior angle theorem.
Notes the difference between an interior and exterior angle in the picture at the top

3. Triangle Sum Theorem
The sum of the interior angles of a triangle is 180.

4. Ex. 1: Solve for x

5. Ex. 2: Solve for x

6. Ex. 3: Solve for x P N W

7. Exterior Angles Theorem
The measure of an exterior angle is equal to the sum of the nonadjacent interior angles.

8. Ex. 4: Solve for x

9. Homework
4.1B #
4.1C #8 - 15