Question

If f(x) is an exponential function where f(4) =17 and f (12.5) = 31, then find the value of f(18.5), to the nearest hundredth.

Answer 1

Solution: f(18.5)=31.47

Step by step solution:
I started by making an equation in slope intercept form- I found the slope, 28/17, with the points (4, 17) and (12.5, 31). Then I found the y intercept, 1, with the point (4, 17). So the equation is y=28/17x+1. Then I just plugged 18.5 where the x is and solved for y

28/17(18.5)+1=y
28/17(37/2)+1=y
1036/34+1= y
30.47+1=y
y=31.47

Keep in mind that 1036/34 is not exactly 30.47 but that 30.47 was rounded to the nearest hundredth

Hope this helps :)