Question 952729

given:

The area of rectangle is {{{A=48cm^2}}}, 
the length {{{L}}} is {{{3}}} times the breadth {{{W}}}: =>{{{L=3W}}} 

find perimeter {{{P}}}:

use {{{A=48cm^2}}} to find {{{W}}}

{{{L*W=48cm^2}}}........substitute {{{3W}}} for {{{L}}}

{{{3W*W=48cm^2}}}

{{{3W^2=48cm^2}}}

{{{W^2=48cm^2/3}}}

{{{W^2=16cm^2}}}

{{{W=sqrt(16cm^2)}}}

{{{highlight(W=4cm)}}}

then, find {{{L}}}

{{{L=3W}}} =>{{{L=3*4cm}}} =>{{{highlight(L=12cm)}}} 

{{{P=2(L+W)}}}...substitute {{{12cm}}} for {{{L}}} and {{{4cm}}} for {{{W}}}

{{{P=2(12cm+4cm)}}}

{{{P=2(16cm)}}}

{{{highlight(P=32cm)}}}