1. Lesson 4-8 Example 3 4-8 Example 3 What is the volume of the triangular prism? 1.Use the Pythagorean Theorem to find the leg of the base of the prism. This leg is the height of the triangular base. a 2 +b 2 =c 2 Use the formula. 16 2 +b 2 =20 2 Substitute the measure of each side. 256+b 2 =400Simplify the exponents.

2. Lesson 4-8 Example 3 4-8 Example 3 What is the volume of the triangular prism? b=12Simplify the square roots. The length of the leg is 12 inches. Take the square root of both sides. b 2 =144Subtract.

3. 2.Next find the area of the base. Lesson 4-8 Example 3 4-8 Example 3 What is the volume of the triangular prism? Use the area of a triangle formula to find the area of the base. Substitute the base and height of the triangle. Multiply. The area of the base is 96 inches.

4. Lesson 4-8 Example 3 4-8 Example 3 What is the volume of the triangular prism? 3.Then find the volume of the prism. V = B × hUse the formula for the volume of a triangular prism. V  96 × 3 Substitute the area of the circle and the height of the prism. V  288Multiply. The volume of the triangular prism is about 288 cubic inches.