Find all values of $x$ such that $x^2 - 5x + 4 = -x^2 - 25x - 14$. If you find more than one value, then list your solutions, separated by commas.
x^2 - 5x + 4 = -x^2 - 25x - 14
2x2 + 20x + 18 = 0
x2 + 10x + 9 = 0
(x + 1)(x + 9) = 0
(x + 1) = 0 ==>> x = –1
(x + 9) = 0 ==>> x = –9
x = –1, –9
.
+92 
