hy guys please assist with this quesiton – Gr 9 algebra question

Simplify the following algebraic expressions:

1. – 6x + 5 + 12x -6
2. 2(x – 9) + 6(-x + 2) + 4x
3. 3×2 + 12 + 9x – 20 + 6×2 – x
4. (x + 2)(x + 4) + (x + 5)(-x – 1)
5. 1.2(x – 9) – 2.3(x + 4)
6. (x2y)(xy2)
7. (-x2y2)(xy2)