## Functions Modeling Change: A Preparation for Calculus, 5th Edition

For $x = \frac{1}{2}$ the answer is $y = \frac{1}{10}$, for $y = -5$ the answer is $x = -25$.
We receive the first result by inserting $x = \frac{1}{2}$ in $x = 5y$: $\frac{1}{2} = 5 y \Rightarrow \frac{1 }{2 \cdot 5} = y \Rightarrow \frac{1}{10} = y$. We receive the second result by inserting $y = -5$ in $x = 5y$: $x = 5 \cdot (-5) \Rightarrow x = - 5 \cdot 5 \Rightarrow x = -25$.