please help in areas

Question

The slant height of a right circular cone is 10 m and its height is 8 m. Find the area of its curved surface.

Answer 1

Let the slant height of a right circular cone be l = 10 m

Let the height of a right circular can be h = 8 m

Let the radius be r = √(10^2 - 8^2)

                              = √(100 - 64)

                              = √36

                              = 6 m

Curved surface area = π * r * l m^2

                                  = π * 6 * 10 m^2

                                  = 60π m^2

Therefore the curved surface area of a right circular cone is 60π m^2.