So let's assume that n years pass. Then the function would be:
[tex]y_n=18\cdot(0.65)^n[/tex]
Now let's assume that another year passes. Then the exponent of the function will be n+1 and we'll have:
[tex]y_{n+1}=18\cdot(0.65)^{n+1}[/tex]
If we take the value of the function at x=n+1 and we divide it by the value of the function one year before we can find the percentage of increase or decrease:
[tex]\frac{y_{n+1}}{y_n}=\frac{18\cdot(0.65)^{n+1}}{18\cdot(0.65)^n}=0.65[/tex]
This means that every year the value of the function is the 65% of the value of the prrevious year. This means that every year there is aa decrease of 100%-65%=35%.
This means that the answer for the first blank space is 35% and the answer for the second is decrease.
