How do i solve this?

How do i solve this? 7. Complete the following. a) Simplify: b) If x + = 7, evaluate the following. x2 ii) x3+2Z 13 8. Show that: a) n2 + 3n+ 2 is even for n e Z. b) n3+ 3n2 + 2n is divisible by 6 for n Z. 9. Fully factorise each of the following expressions. a) 6x2y 36xy2z 24yz2 b) 18x3— 50xy2 c) 3a4 -- 24ab3 d) ax2 — bx2—a+ b ejN9x2(x3 — 1) — 4(x3 — 1) J 52 j06ab — 9az 8bp + 12ap