# Math Help - Exponential function - regularly spaced points

1. ## Exponential function - regularly spaced points

"An exponential function has f(8) = 13 and f(11) = 26. Find another value of f(x) using the pattern followed by regularly spaced points."

I found the equation is 2.05*1.26^x using my calculator, however I'm not sure how to use this showing work... ?

2. I would suggest using the model $y = A\times b^x$ or $y= Ae^{bx}$

Either way substitute your two points in to solve A and b simultaneously.