Question 617070
Let {{{ x }}} = the width
{{{ x + 10 }}} = the length
{{{ x*( x + 10 ) = 200 }}}
{{{ x^2 + 10x = 200 }}
Complete the square
{{{ x^2 + 10x + (10/2)^2 = 200 + (10/2)^2 }}}
{{{ x^2 + 10x + 25 = 225 }}}
{{{ ( x + 5 )^2 = 15^2 }}}
Take the square root of both sides
{{{ x +5 = 15 }}}
{{{ x = 10 }}}
{{{ x +10 = 20 }}}
The dimensions are 10 ft x 20 ft