Question

The length of a rectangle is twice its width. The perimeter is 60 ft Find its area.

a) A=200 ft²
b) A= 10 ft²
c) A= 100 ft ²​

Answer 1

A=200 ft²

Explanation:

let the Length be L and the Width be W

We know that Perimeter = Length + Length + Width + Width

or,

Perimeter = 2(L + W)

given that Perimeter = 60 ft,

60 = 2(L+W) (divide both sides by 2)

60/2 = (L+W)

L + W = 30 ---------------------eq 1

we are further given that the length is twice the width, or,

L = 2W ---------------------- eq 2

substituting eq2 into eq 1,

L + W = 30

(2W) + W = 30

3W = 30

W = 10 (substitute this into eq 2)

L = 2W

L = 2(10)

L = 20

Area = Length x Width

= 20 x 10

= 200 ft²