Question

How do you determine if the equation `y=100(0.9)^x` represents exponential growth or decay?

Answer 1

Decay

Explanation:

Draw the graph with the graphing tool.

We observe that `y` starts with a very large value.

Thereafter for increasing values of `x` the value of `y` decreases and approaches `0` asymptotically. Hence it depicts decay.

graph{y=100(0.9)^x [-90.7, 549.3, -79.4, 240.6]}