Question 318419
For a rectangle,
{{{P=2L+2W=200}}}
{{{L+W=100}}}
.
.
.
{{{L=W+20}}}
Substitute into the perimeter equation,
{{{W+20+W=100}}}
{{{2W=80}}}
{{{highlight(W=40)}}}
{{{L=40+20}}}
{{{highlight(L=60)}}}