Question 23215
Let x = side of the square
x+10 = length of the rectangle
x-8 = width of the rectangle


Area of Square = Area of Rectangle
{{{x^2 = (x+10)(x-8) }}}
{{{x^2 = x^2 + 2x - 80}}}


Subtract {{{x^2}}} from each side.


{{{0= 2x - 80 }}}
{{{80=2x}}}
{{{x=40}}} meters


Check:

Area of square = {{{x^2 = 40^2 = 1600 m^2}}}
Area of rectangle = {{{(x+10)*(x-8) = 50*32 = 1600 m^2}}}


R^2 at SCC