Answer
See the graph below.
Work Step by Step
As $y=ab^x\rightarrow 0$ when $x\rightarrow -\infty$ where $b>1$, let's consider a function in the form
$$y=ab^x+3,b>1.$$
A plot of such a function is shown below.
$f(x) \rightarrow 3$ as $x \rightarrow-\infty$
