1. Let's clarify the concept of putting an expression "in y." Usually, when dealing with a function or equation, we write it in the form $y = f(x)$ to explicitly indicate the output $y$ in terms of the input $x$. 2. However, it's not always mandatory to write the equation explicitly as $y=...$. You can work with the equation implicitly or solve it for other variables as needed. 3. For example, instead of $y = 2x +3$, you can write the equation as $2x - y = -3$, which implicitly relates $x$ and $y$ without isolating $y$. 4. When graphing or analyzing functions, isolating $y$ often helps to understand its behavior clearly, but other approaches exist, like parametric forms, implicit differentiation, or working directly with expressions. 5. If you specify which equation or problem you're referring to, I can show you alternative ways to approach or solve it without necessarily putting it in the form $y=...$.