Answer: Choice D) y = 35(0.35)^x
Explanation:
The general exponential function
y = a*b^x
has the base b determine if the function curve grows or decays
If b > 1, then we have exponential growth
if 0 < b < 1, then we have exponential decay
In the case of choice D, we have a = 35 as the starting term and b = 0.35 as the base of the exponent. By the rule above, we have exponential decay here. Equate 1+r to 0.35 and we see that 1+r = 0.35 solves to r = -0.65 so we have 65% decay going on. Meaning that each time x increases by 1, the amount drops by 65%
