1. **State the problem:** Solve for $y$ in the equation $X = 17 - 4y$. 2. **Formula and rules:** To isolate $y$, we need to rearrange the equation by moving terms and dividing both sides by the coefficient of $y$. 3. **Isolate $y$:** $$X = 17 - 4y$$ Subtract 17 from both sides: $$X - 17 = -4y$$ 4. **Divide both sides by $-4$ to solve for $y$:** $$\frac{X - 17}{-4} = y$$ Show cancellation: $$y = \frac{\cancel{X - 17}}{\cancel{-4}}$$ 5. **Final answer:** $$y = \frac{17 - X}{4}$$ This means $y$ is equal to the difference between 17 and $X$, divided by 4.