1. **Problem:** Solve the equation $y + 7 = 12$ for $y$. 2. **Formula and rules:** To solve for $y$, isolate the variable by performing inverse operations. Here, subtract 7 from both sides to cancel the +7. 3. **Step-by-step solution:** 1) Start with the equation: $$y + 7 = 12$$ 2) Subtract 7 from both sides to isolate $y$: $$y + \cancel{7} - \cancel{7} = 12 - 7$$ 3) Simplify the right side: $$y = 5$$ 4. **Explanation:** We used the subtraction property of equality, which states that subtracting the same number from both sides keeps the equation balanced. This isolates $y$ and gives the solution. **Final answer:** $y = 5$