We are not sure what you mean by the expression (2x)3 so we have two responses for you.
Response 1: (2x)3 means (2x) times 3 .
When asked to simplify a question, you need to look for a potential operation. Observe this similar problem;
7(3X) (because there is no +/- sign, we can rule this out also, division requires a sign)
7(3x) = 7 * (3x) Brackets are used instead of a sign because the variable 'x' can cause confusion)
= 7 * 3x
Response 2: (2x)3 means (2x) to the power 3, or (2x)3.
I'm going to solve a similar problem as Melanie did.
(5x)4 = (5x) * (5x) * (5x) * (5x) where * is multiplication.
(5x) * (5x) * (5x) * (5x)
= 5 * x * 5 * x * 5 * x * 5 * x
= 5 * 5 * 5 * 5 * x * x * x * x
= 54 * x4
= 625 * x4