SOLUTION: a rectangle is three times as long as it is wide. If its length and width are both decreased by 2 cm, its area is decreased by {{{ 36 cm^2 }}}. I Have to find its original dimensio
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Question 461531: a rectangle is three times as long as it is wide. If its length and width are both decreased by 2 cm, its area is decreased by . I Have to find its original dimensions. I don't understand how to put it into an equation or how to sketch it. If you could help me, it would be greatly appreciated. Thank you. Answer by graphmatics(170) (Show Source):
You can put this solution on YOUR website! Let x be how wide the rectangle is. Then 3*x is how long the rectangle is. If a rectangle is a units long and b units wide the a*b is the area of the rectangle. So for this rectangle to decrease the width and longness of the rectangle by 2 cm we must have that
(x-2)*(3x-2) = (x)*(3*x) - 36
3*x*x - 2*x -6*x +4 = x*3*x - 36
-8*x = -40
x = 5
So the width of the rectangle is 5 and the rectangle is 15 cm long.
