SOLUTION: The length of a rectangle is 5 metres shorter than three times the width. If the perimeter is 54 metres, what are the dimensions of the rectangle?

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Question 884793: The length of a rectangle is 5 metres shorter than three times the width. If the perimeter is 54 metres, what are the dimensions of the rectangle?
Answer by josgarithmetic(39618) About Me  (Show Source):
You can put this solution on YOUR website!
L for length and w for width.
L=-5+3w and 2w+2L=54.

The perimeter equation can easily be simplified here: w+L=27.
The L&w relationship can be restated L-3w=-5, or 3w-L=5.

SYSTEM
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3w-L=5
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w+L=27
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Ready for Elimination Method to start.
4w=32
w=8.

Now return to the original equation formula for L.
L=-5+3w
L=-5+3*8
L=-5+24
L=19.

ANSWER: Length 19, width 8.