1. Section 8-3 The Converse of the Pythagorean Theorem

2. Theorem 8-3 If the square of one side of a triangle is equal to the sum of the squares of the other two sides, then the triangle is a right triangle.

3. Examples: Determine if the given measures are measures of the sides of a right triangle. 1. 14, 48, 50 2. 50, 75, 85 3. 15, 36, 39 4. 45, 60, 80 Yes No Yes No

4. Some Common Right Triangle Lengths: 3, 4, 5 5, 12, 13 8, 15, 17 7, 24, 25

5. Theorem 8-4: If, then and is acute Example:

6. Theorem 8-5: If, then and is obtuse Example:

7. Examples: Classify each triangle with sides of the given lengths as acute, right, or obtuse. 1. 5, 12, 14 2. 6, 7, 8 3. 4. 1, 3, Obtuse Acute Right