Question 857937
Let:

x     - be the width
3x+2  - be the length

P=2w+2l

Therefore,

{{{100=2(x)+2(3x+2)}}}
{{{100=2x+6x+4}}}
{{{100=8x+4}}}
{{{96=8x}}}
{{{12=x}}}

Therefore the width is 12 feet, and the length is 38 feet.

Hope that helps! :)

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