Question 1019712
Let {{{ x }}} = the width
{{{ 2x }}} = the length
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Use the formula for perimeter:
{{{ 48 = x + x + 2x + 2x }}}
{{{ 6x = 48 }}}
{{{ x = 8 }}}
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The 2 shorter sides add up to:
{{{ 2x = 2*8 }}}
{{{ 2x = 16 }}} ft
The 2 longer sides add up to:
{{{ 4x = 32 }}} ft
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Let {{{ C }}} = the cost to build the pen
{{{ C = 2.25*32 + 4.25*16 }}}
{{{ C = 72 + 68 }}}
{{{ C = 140 }}}
$140