I find it easier just to graph this sort of question rather than multiply it all out.
x = 3.5
_____
(x^2 +2x +1) -(x^2 -6x +9) = 20
.. 8x -8 = 20
.. x = 28/8 = 3.5
x = 3.5
_____
(x^2 +2x +1) -(x^2 -6x +9) = 20
.. 8x -8 = 20
.. x = 28/8 = 3.5
