Answer
$y=-50\left(\frac{1}{5}\right)^{x}$
Work Step by Step
Exponential function is of the form
$y=ab^{x}$ where $a\ne0$, $b\ne1$ and $b\gt0$.
From the table of values,
$\text{y-intercept}=-50=a$
The $y$-values change by a factor of $\frac{1}{5}$ as $x$ increases by $1$. So, $b=\frac{1}{5}$.
An exponential function represented by the table is $y=-50\left(\frac{1}{5}\right)^{x}$.
