Question 134610
Formula for perimeter: {{{P=2L + 2W}}}


Width is 2 inches shorter than length, so:  {{{W=L-2}}}


Substituting:


{{{P=2L + 2(L-2)}}}
{{{P=4L-4}}}


Given P = 80,


{{{4L-4=80}}}
{{{4L=84}}}
{{{L=21}}}, hence {{{W=19}}}


Check:
{{{P=2(21) + 2(19)=42+38=80}}} Answer checks.