Question

9. The length of a rectangle is three times its width. It the perimeter is 84 find the length of the rectangle
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Answer 1

Step-by-step explanation:

let,

the breadth is x

so , the length is 3x .

perimeter = 2(l+b) = 2(x+3x ) = 8x

According to question ,

$8x = 84 \\ 2x = 21 \\ x = \frac{21}{2}$

so the breadth is 21/2 = 10.5

and the length is 3× 10.5 = 31.5