We are given the following exponential function
Let us have a look at the graph of this exponential function
From the graph, it might look that the graph is touching the x-axis but in reality, it does not.
The graph keeps on increasing as x gets larger and larger.
On the other hand, the graph keeps on decreasing as x gets smaller and smaller, but it never becomes equal to 0
This is known as "horizontal asymptote"
A horizontal asymptote is a horizontal line that the graph is trying to approach but it never actually touches it.
Therefore, the graph of the exponential function approaches the x-axis, but never actually touches the x-axis since it is a horizontal asymptote.