Final answer:
The original expression is simplified to 0. None of the given expressions are equivalent.
Step-by-step explanation:
The expression 8 1/2x 1/2 3 1/2x-2x can be simplified by using the rules of multiplication and division. We can start by multiplying the fractions 1/2 and 1/2, which results in 1/4.
Next, we can multiply the whole numbers 8 and 3 to get 24. Finally, we can simplify the expression 2x-2x to 0. Putting it all together, the simplified expression is 24(1/4)(0), which equals 0. Therefore, none of the given expressions (1) 8x - 4x, (2) 8x + 4x, (3) 8x - 2x, or (4) 8x + 2x are equivalent to the original expression.