I need some help on figuring out how to solve these equations, the directions say the problems represent a mix of linear, quadratic, and third degree polynomial equations. Here they are:

1.) y^3 +3y^2 - 4y - 12= 0

2.) 2x^3 + 3x^2 = 8x +12

3.) 2a (a+1) = a^2 +8

4.) 2x^3 + x^2 = 32x +16

Thanks for your help! It's appreciated!