Question

Which of the following expressions represents the lateral area of a right cone with r units as the radius of its base, l units as its slant height, and h units as its height?

A. pirh
B. 2pirh
C. pir2
D. pirl

Answer 1

Option D.
`\pi rl\ units^(2)`

Explanation:

we know that

The lateral area of a cone is equal to

`LA=\pi RL`

where

R is the radius of the base of the cone

L is the slant height of the cone

In this problem we have

`L=l\ units`

`R=r\ units`

substitute

`LA=\pi (r)(l)=\pi rl\ units^(2)`

Answer 2

The expressions that represents the lateral area of a right cone with r units as the radius of its base, l units as its slant height, and hunits as its height is
pirl
as it finds the lateral area not the whole area of cone
so correct option is D
hope it helps