Question

The solid below was made by cutting a cone-shaped hole out of a cylinder. The surface area of the resulting composite solid is square cm. Write your answer in terms of pi.

Answer 1

*see attachement below for the diagram

Answer:

(252π + 20) cm²

Explanation:

The surface area of the resulting solid = curved surface area of the cylinder + area of 1 base of the cylinder + 2(slant height of the cone)

✔️Curved surface area of cylinder = 2πrh

r = ½(12) = 6 cm

h = 18 cm

C.S.A = 2*π*6*18 = 216π cm²

✔️Area of 1 base = πr²

r = ½(12) = 6 cm

Area = π*6²

Area = 36π

✔️Slant height of the cone = 10 cm

✅The surface area of the resulting solid = 216π + 36π + 2(10)

= (252π + 20) cm²