Question 277221
P=perimeter
L=length
W=width
GIVEN: P=640 L=3W P=2L+2W
USE SUBSTITUTION
{{{P=2L+2W}}} solve for W
{{{640=2(3W)+2W}}}distribute
{{{640=(6W)+2W}}}add
{{{640=8W}}}divide
{{{highlight(80=W)}}}
___
if W=80 then:
{{{L=3W}}}
{{{L=3(80)}}}
{{{highlight(L=240)}}}