Question 1020011
20 ft of the rectangle needs no fence, but
the opposite side needs 20 ft.
Let {{{ x }}} = the length in ft of the adjacent
sides.
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Let {{{ L }}} = length of fence needed
{{{ L = 20 + 2x }}} ft
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{{{ 680 }}} ft2 = area of field
{{{ 20x = 680 }}}
{{{ x = 34 }}} ft
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{{{ L - 20 + 2x }}} ft
{{{ L - 20 + 2*34 }}} ft
{{{ L = 20 + 68 }}}
{{{ L = 88 }}}
88 ft of fencing is needed