Question 1138281
Let {{{ x }}} = the widths of the added strips
{{{ 2x }}} = the width that is added to the sides
convert yards to feet
{{{ 12 + 2x )*( 18 + 2x ) = 2*12*18 }}}
{{{ 216 + 36x + 24x + 4x^2 = 432 }}}
{{{ 4x^2 + 60x - 216 = 0 }}}
{{{ x^2 + 15x - 54 = 0 }}}
Use quadratic formula
{{{ x = (-15 +- sqrt( 15^2-4*1*(-54) ))/(2*1) }}}
{{{ x = (-15 +- sqrt( 225 + 216 ))/2 }}}
{{{ x = ( -15 + sqrt( 441 ) )/2 }}}
{{{ x = ( -15 + 21 )/2 }}}
{{{ x = 3 }}} ft
This is 1 yd so the strip is 1 yd wide.
I converted to feet thinking there might
be fractions of a yd in answer
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check:
{{{ ( 12 + 2x )*( 18 + 2x ) = 432 }}}
{{{ ( 12 + 2*3 )*( 18 + 2*3 ) = 432 }}}
{{{ 18*24 = 432 }}}
{{{ 432 = 432 }}}
OK