PLEASE HELP!!! RIGHT AWAY PLEASE!!

Which expressions are equivalent?

Select ALL answers that are correct.

1. 24x^6−18x^5=6x^5(4x−3)
2. 20x^3+12x^2=4x^2(5x+3)
3. 12x^5+8x^3=2x^3(6x2+4)
4. 18x^4−12x^2=6x(3x^3−2x)