5x2 + x + 7 cannot be simplified.
3x
35 + 40x + 5x2 = 5(7 + 8x + x2) = 5(7 + x)(1 + x)
Divide all terms by 5 and so x^2+6x-55 = (x+11)(x-5) when factored
X= -2
x + 5 + 4 = x + 9
x(x + 2)
15
You can expand the first expression in parentheses, then add or subtract like terms.
- - x + 3 = x + 3
-9
(x+2)/(x+2) = 1x equals infinity
x - 2x + 3 = 3 - x