Stuck on problem

Find a formula for the exponential function passing through the points  (-1,2/3) and (1,6) Help much apprieciated can't figure this one out.

Here's another approach

We have the form

y  = ab^x

When   x  = -1, y = 2/3

When x  = 1, y  = 6

So we have that

2/3  = ab^(-1)      (1)

6  =  ab^(1)   ⇒  ab  = 6   ⇒  b = 6/a      (2)

Sub (2)   into (1)   and we have that

(2/3) =  a  ( 6/a)^(-1)      

2/3  =  a ( a /6)      multiply through by 6

4  =  a^2      take the positive root

2  = a

So    b  =   6/2  =  3

So....the function is

y = 2 (3)^x

Here's a praph   :  

https://www.desmos.com/calculator/mmoq0kzrez