Question 1048751
Length = {{{ x + 3 }}}
Width = {{{ x - 7 }}}
Let the perimeter = {{{ P }}}
Let the area = {{{ A }}}
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The formula for perimeter is:
[ twice the length ] + [ twice the width ] = [ perimeter ]
{{{ P = 2*( x+3 ) + 2*( x -7 ) }}}
{{{ P = 2x + 6 + 2x - 14 }}}
{{{ P = 4x - 8 }}}
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The formula for area is:
[ length ] x [ width ] = [ area ]
{{{ A = ( x + 3 )*( x - 7 ) }}}
{{{ A = x^2 + 3x - 7x - 21 }}}
{{{ A = x^2 - 4x - 21 }}}