Question

Question 12 the length of a rectangle is three times its width. if the perimeter of the rectangle is 40 m , find its area.

Answer 1

Let the width be x.

Length = 3x

Perimeter = 40 

2*(L + W) = 40

L + W = 20

3x + x = 20

4x = 20

x = 5

Hence, 

Length = 15 m

Width = 5 m

Area = L*W = 15 * 5 = 75 sq. m

Answer 2

Answer:

The area of the rectangle is 75 squared meters.

Step-by-step explanation:

Width of the rectangle = w

Length of the rectangle = l = 3w

Perimeter of the rectangle = P = 40 m

Perimeter of the rectangle = 2(l+w)

$2(l+w)=40 m$

$2(3w+w)=40 m$

$8w=40 m$

$w=\frac{40 m}{8}=5 m$

$l=3w=3\times 5 m=15 m$

The area of the rectangle ,A= l × w

$A = 5 m\times 15 m = 75 m^2$

The area of the rectangle is 75 squared meters.