1. **State the problem:** Given values $s = -2$, $t = 4$, and $y = 5$, we need to understand what to do with these variables. Since no specific operation or equation is provided, let's consider a simple example: calculate the expression $s + t + y$. 2. **Formula used:** The sum of variables is given by $$s + t + y$$. 3. **Substitute the values:** Replace $s$, $t$, and $y$ with their given values: $$-2 + 4 + 5$$ 4. **Simplify step-by-step:** $$(-2 + 4) + 5 = 2 + 5 = 7$$ 5. **Final answer:** The sum of $s$, $t$, and $y$ is $$7$$.