Question 851120
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The length of a rectangle is twice it's width. If it's perimeter is 54cm, find its length. Explain!

Solution:
Let the width be x cm
Then the length = 2*x cm
Perimeter = 2*(length + width) = {{{2*(x + 2*x)}}} = {{{2*3*x}}} = {{{6*x = 54}}}

Solving, {{{x = 54/6 = 9}}}

So width = {{{highlight(9)}}} cm and length = {{{highlight(18)}}} cm

Check: Perimeter = {{{2*(9+18) = 54}}}. Correct!

:)

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