Answer:
It represents growth, and the percentage rate of increase is of 8%
Step-by-step explanation:
Exponential equation:
An exponential equation has the following format:
[tex]A(t) = A(0)(1 + r)^t[/tex]
In which A(0) is the initial amount and r is the rate of change, as a decimal. If positive, it is growth, if negative, it is decay.
In this question:
[tex]y = 21(1.08)^x[/tex]
So
[tex]1 + r = 1.08[/tex]
[tex]r = 0.08[/tex]
Since r is positive, it represents growth, and the percentage rate of increase is of 0.08*100% = 8%