Rectangle

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Rectangle

by odod » Wed Apr 01, 2009 11:05 am
Hello,

Please see the attachment and advise if you can figure out how to solve it.


Thanks.

OA - A
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by relic » Wed Apr 01, 2009 11:14 am
If the sides of the rectangle are y and z, then the area of the shaded region will be the area of the rectangle minus the area of the unshaded triangle,

5x^2 = yz - 0.5*x*2x = yz - x^2

solve for the area of the rectangle, yz

yz = 6x^2

The answers represent potential sides of the rectangle, so we seek the answer whose product is 6x^2. Only answer A gives such a result.

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by HumbleMe » Wed Apr 01, 2009 1:11 pm
Area of unshaded area is = (2x*x)/2 = x^2
Total area of rectangle = 5x^2 + x^2 = 6x^2

Out of given option, only A makes sure that area is 6 x^2. Hence A