Question 1087935
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<U>Answer</U>. 6 and 2.5 ft.


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To solve it <U>MENTALLY</U>, consider rectangle with doubled dimensions.

Then the area is 15*4 = 60 ft^2, and the difference L - W = 7 ft.


Now find (<U>MENTALLY</U>) two factors of 60 that differ in 7 (=2*3.5) ft.


They are 12 and 5.


Now divide 12 and 5 by 2 to return to the original dimensions.


You will get 6 and 2.5.
</pre>

Solved (<U>MENTALLY</U>).



The alternative way is to solve a quadratic equation with decimal coefficients.