y=ab^x

I have a table with exponents given (x) and y given. I need to find a and b.
x y
0 300
2 48
3 19.2
4 7.68

What is the formula to solve a and b?

write y=a b^x replacing y and x with the values in your table. That gives you four equations. The first equation,

300 = ab^0

is an intercept (x=0) and will give you the value of "a"

the second equation, 48 = ab^2, can be solved because you already know "a".

The other two equations that you can make are not really needed. Use them to make sure your answer is correct.

19.2 = a b^3
7.68 = a b^4