Question

The length of a rectangle is three times its width. If the perimeter is 84 m, find the length of the rectangle

Answer 1

let the width be X :. the length= 3X

perimeter of rectangle = 84cm

perimeter=2(length+width)

p=2(X+3X)

p=2X +6X

84= 8X

X =84÷8

X=10.5(width)

3X=31.5(length)

Answer 2

Let the width be x and perimeter be 3x(3times means multiplying)
Perimeter=84m
ATQ,
$2(l + b) = 84m$
2(x+3x)=84
2*4x=84
8x=84
x=84/8
x=10.5
Therefore length=3x
=3*10.5=31.5m
=width=x=10.5m
Hope this answer is helped