1. Lesson 5 Menu 1.Find the surface area of the regular pyramid shown. Round to the nearest tenth if necessary. 2.Find the surface area of the regular pyramid shown. Round to the nearest tenth if necessary. 3.What is the slant height of a square pyramid with base lengths of 15 inches and height of 10 inches?

2. Lesson 5 MI/Vocab circular cone right cone oblique cone Find lateral areas of cones. Find surface areas of cones.

3. Lesson 5 KC1

4. Lesson 5 Ex1 ExploreWe are given the altitude and the diameter of the base. We need to find the slant height of the cone. Lateral Area of a Cone

5. Lesson 5 Ex1 PlanThe radius of the base, height, and slant height form a right triangle. Use the Pythagorean Theorem to solve for the slant height. Then use the formula for the lateral area of a right circular cone. Lateral Area of a Cone

6. Lesson 5 Ex1 Next, use the formula for the lateral area of a right circular cone. Lateral Area of a Cone Solve Write an equation and solve for. Simplify. Pythagorean Theorem Take the square root of each side. Lateral area of a cone Use a calculator.

7. Lesson 5 Ex1 Answer:The lateral area is approximately 31.8 square inches. Lateral Area of a Cone CheckUse estimation to check the reasonableness of this result. The lateral area is approximately 3 ● 1.25 ● 8 or 30 square inches. Compared to the estimate, the answer is reasonable.

8. A.A B.B C.C D.D Lesson 5 CYP1 A.73.4 in 2 B.70.7 in 2 C.141.4 in 2 D.146.7 in 2 A hat for a child’s birthday party has a conical shape with an altitude of 9 inches and a diameter of 5 inches. Find the lateral area of the birthday hat. Round to the nearest tenth.

9. Lesson 5 KC2

10. Lesson 5 Ex2 Surface Area of a Cone Find the surface area of the cone. Round to the nearest tenth. Answer:The surface area is approximately 20.2 square centimeters. Surface area of a cone Use a calculator.

11. Lesson 5 CYP2 1.A 2.B 3.C 4.D A.124.6 cm 2 B.80.2 cm 2 C.63.6 cm 2 D.20.2 cm 2 Find the surface area of the cone. Round to the nearest tenth.