First, we are going to find the number of years form 2005 to 2014; to do it, we are going to subtract 2005 from 20014:
Number of years = 2014 - 2005 = 9 years
Now, we are going to replace
![x](https://img.qammunity.org/2019/formulas/mathematics/college/lhtxftojjkzsmo3o2h4ilq8naohracejui.png)
with 9 in our function:
![f(x)=75(1.2)^x](https://img.qammunity.org/2019/formulas/mathematics/middle-school/72zha6mv383gm5i8snv9qojpzz9xn8rwsu.png)
![f(x)=75(1.2)^9](https://img.qammunity.org/2019/formulas/mathematics/middle-school/x5n4brxk2pgwiwpebkfuk0zzu15t3sk5n6.png)
![f(x)=386.98](https://img.qammunity.org/2019/formulas/mathematics/middle-school/kfrv9uavxlxl2qqvvanustwccn350dvg6f.png)
Rounded to the nearest integer:
![f(x)=387](https://img.qammunity.org/2019/formulas/mathematics/middle-school/r0thfrtpe1tfccb1w7ax0swlczm6uz87ds.png)
We can conclude that in the year 2014 will be approximately
387 rainbow tout in the lake.