Question

How do you determine if the equation `y=2^x` represents exponential growth or decay?

Answer 1

It represents a growth.

Explanation:

You can try observing what happens to `y` when `x` increases.
Say that you choose for `x` the increasing values `1 and 3`;
You'll get for `y` the increasing values `2 and 8`;
What if you are in the negative range?
Let us choose increasing negative `x` values, say, `-3 and -1`;
You get for `y` the increasing values `0.125 and 0.5`.