Question 418780
width = x feet

length = x + 10 feet


area = length x width


56  = x(x+18)

{{{ 56  = x^2 + 10x}}}

{{{ x^2 + 10x - 56 = 0}}}

{{{(x+14)(x-4) = 0}}}

==>  x + 14 = 0     or   x-4 = 0


==> x  = -14    or   x = 4


since length and width cannot be a negative number, you can ignore the negative value u got for x

==> width = 4 feet
so length = 4 + 10 = 14 feet