Answers

2016-08-02T06:55:54+08:00
P=2(l+w);

86=2(l+w);
l+w=43;
l=43-w.........a;

A=lw;
lw=450........b.
43-w]w=450;

-w^2+43w=450;
w^2-43w+450=0

find w, by quadratic formula;
w=
0