Question 1054038
{{{L=6W-4}}}
and
{{{P=2L+2W=20}}}
{{{L+W=10}}}
Substituting,
{{{6W-4+W=10}}}
{{{7W=14}}}
{{{W=2}}}{{{cm}}}
Then,
{{{L=6(2)-4}}}
{{{L=12-4}}}
{{{L=8}}}{{{cm}}}