Question 178025
Let {{{p}}}= perimeter
Let {{{w}}}= width
Let {{{l}}}= length
{{{p = 2w + 2l}}}
given:
{{{p = 84}}} ft
{{{w/l = 2/5}}}
multiply both sides by {{{5*l}}}
{{{5w = 2l}}}
{{{w = (2/5)*l}}}
{{{p = 2*(2/5)*l + 2l}}}
{{{84 = (4/5)*l + 2l}}}
Multiply both sides by {{{5}}}
{{{420 = 4l + 10l}}}
{{{14l = 420}}}
{{{l = 30}}}
{{{w = (2/5)*l}}}
{{{w = (2/5)*30}}}
{{{w = 12}}}
The length is 30 ft and the width is 12 ft
check:
{{{p = 2w + 2l}}}
{{{p = 2*12 + 2*30}}}
{{{p = 24 + 60}}}
{{{p = 84}}}
OK