Question 920434
given:
*square* {{{L[s]=(2x+2)cm }}}    =>    {{{P[s]=4(2x+2)cm }}}   
*Rectangle* {{{W[r]=(x+1)cm }}}   => {{{P[r]=2(x+1)cm+2(x+3)cm }}}
{{{P[s]=P[r]}}}
Show that the length of the rectangle is {{{L=(3x+1)cm}}}

since {{{P[s]=P[r]}}} we have

if {{{W[r]=(x+1)cm }}} and {{{L=(3x+1)cm}}}=>{{{P[r]= 2(3x+1)cm+2(x+3)cm }}}

and it is equal to {{{P[s]=4(2x+2)cm }}}   

so,

{{{4(2x+2)cm= 2highlight((3x+1))cm+2(x+3)cm}}} ...solve it and see if left side is equal to right side:


{{{8x+8cm= 6x+2cm+2x+6cm}}} 


{{{8x+8cm=8x+8cm}}} ...{{{highlight(true)}}}, so the length of the rectangle is  {{{highlight((3x+1))cm}}}