To interpret the equation \( \frac{x}{8} = \frac{3(x+4)}{2} \) using grouping symbols and identify which expression represents a product, we can rewrite the equation clearly:
The right side of the equation is \( \frac{3(x + 4)}{2} \).
Here, the expression \( 3(x + 4) \) consists of the number 3 multiplied by the quantity \( (x + 4) \).
Thus, the expression that represents a product is \( 3(x + 4) \) since it involves multiplication.
So, the answer is \( 3(x + 4) \).