Respuesta :

ChoiSungHyun

Step-by-step explanation:

f(x) = a * b^x

We have the following information:

f(0) = a * b^(0) = 15. => a * 1 = 15, a = 15.

f(1) = a * b^(1) = 9. => a * b = 9, (15) * b = 9, b = 0.6.

Hence f(x) = 15 * 0.6^x.