Question 1097599
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<U>1 - Mental solution</U>


<pre>
The original area = 12*8 = 96 sq. m.

The doubled area = 96*2 = 192 sq. m.


Now I should factor 192 into the product of two factors with the difference between them equal to 12-8 = 4:

192 = 96*2 = 48*4 = 24*8 = 12*16     (!)  Ops (!!!)


<U>Answer</U>. The new dimensions are 16 and 12, and the increase of each dimension is 4 m.
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<U>2 - Algebra solution</U>


<pre>
(12+x)*(8+x) = 2*12*8,   or

x^2 + 40x - 96 = 0,

(x+36)*(x-4) = 0,


and the only positive root x= 4 is the solution to the problem.
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Solved.