Simplify the following algebraic expressions.

-6x + 5 + 12x -6


2(x - 9) + 6(-x + 2) + 4x


3x2 + 12 + 9x - 20 + 6x2 - x


(x + 2)(x + 4) + (x + 5)(-x - 1)


1.2(x - 9) - 2.3(x + 4)


(x2y)(xy2)


(-x2y2)(xy2)