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The length of a rectangle is three times its width, if the area of the rectangle is 108cm2, find its perimeter

User BarrettJ
by
4.5k points

2 Answers

10 votes

Answer:

48cm

Explanation:

User Tomas Di Domenico
by
4.4k points
5 votes

Answer:

The perimeter of rectangle is 48 cm.

Explanation:

First, you have to form an expression for the length and the width. Let x be the width :

width = x cm

length = 3 × x = 3x cm

Then, you have to apply area of rectangle formula, A = length × width to find the value of x.Let area equals to 108 :

A = length × width

108 = 3x × x

3x² = 108

x² = 108 ÷ 3

x² = 36

x = √36

x = 6 cm

Lastly, you have to find perimeter :

length = 3 × 6 = 18 cm

width = 6 cm

Perimeter = 2(length + width)

P = 2(18 + 6)

P = 2(24)

P = 48 cm

User Yandry
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4.8k points