Question 1086902
Let {{{ x }}} be the length in each case
Let {{{ A }}} = the area in each case
{{{ 2x + 20 = 40 }}}
{{{ 2x = 20 }}}
{{{ x = 10 }}}
{{{ A = 10*10 }}}
{{{ A = 100 }}}
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{{{ 2x + 22 = 40 }}}
{{{ 2x = 18 }}}
{{{ x = 9 }}}
{{{ A = 9*11 }}}
{{{ A = 99 }}}
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{{{ 2x + 24 = 40 }}}
{{{ 2x = 16 }}}
{{{ x = 8 }}}
{{{ A = 8*12 }}}
{{{ A = 96 }}}