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The perimeter of a rectangle is 30 inches. If it's length is three times it's width, find the dimensions

User Cmcromance
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2 Answers

4 votes
let the width be x.

length = 3*width = 3*x = 3x.

Perimeter, P = 2*(l + w), P = 30 inches.

P = 2*(l + w)

30 = 2*(3x + x)

30 = 2*(4x)

30 = 8x

8x = 30

x = 30/8 = 15/4 = 3.75

Dimensions, w =x = 3.75 inches, length = 3x =3*3.75 = 11.25 inches.

So dimensions of the rectangle is 11.25 inches by 3.75 inches.

Hope this helps.
User Jiayao Yu
by
5.9k points
1 vote
Lets x is width
3x is length

P = 2(W+L)
30 = 2(x+3x)
30 = 2(4x)
30 = 8x
so x = 30/8 = 3.75

3x = 3(3.75) = 11.25

answer: width = 3.75 inches and length = 11.25 inches
User Sergio Martins
by
6.5k points