Mathematics for IGCSE & O level - Algebraic Manipulation (Section 8 - No. 6)

Which expressions are equivalent?

3x + 2x and 5x

4(x+2) and 4x + 2

x^2 + 2x and x(x+2)

x - 2 and 2 - x

3x + 2x is 5x. x^2 + 2x and x(x+2) has the same value when applying distributive property.