The expression \( y - 3\left(\frac{1}{2}\right) \) represents a linear equation in terms of \( y \) but is not in a standard form that indicates growth or decay. Instead, it suggests a specific transformation or shift of the variable \( y \).
However, if you meant to refer to an exponential function such as \( y = 3 \left(\frac{1}{2}\right)^x \), then it indicates decay, since \(\frac{1}{2}\) is a fraction less than 1. Exponential functions with a base between 0 and 1 represent decay because the value decreases over time (i.e., as \( x \) increases).
If you could clarify the expression you're referring to, I would be happy to provide a more accurate interpretation!