Answers

2016-07-26T21:04:57+08:00
A=LxW;

84=LxW;
25=2l+2w;
l+w=25/2;

l=25/2-w;
84={25/2]-w}(w);
84=25/2)w-w^2;
x (2);

168=25w-2w^2;
2w^2-25w+168=0;

just double check the given ^-^

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