Question 1112755
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The length of a rectangular lot is three times its width, if the length is increased by 5 meters and the width is decreased by 2 meters the {{{cross(original)}}} NEW area of the lot will decrease by 21 square meter. Find the dimension of the lot.
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Original dimensions:
3w and w


New dimensions:
3w+5 and w-2


New lot area decreased by 21 square meters.
{{{3w*w-(3w+5)(w-2)=21}}}

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{{{3w^2-(3w^2-w-10)=21}}}
{{{3w^2-3w^2+w+10=21}}}
{{{w+10=21}}}
{{{highlight_green(w=11)}}}------width of the original lot.
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{{{highlight_green(33)}}}------------length of the original lot.