Find a formula for the exponential function passing through the points (-3,5/27) and (1,15).

Question

f(x)=

Answer 1

y = a*b^x
a/b^3 = 5/27
ab = 15
divide, and yo have 1/b^4 = 1/81
b = 3
so, a = 5
y = 5 * 3^x

Answer 2

Find a formula for the exponential function passing through the points (-1,4/5) and (3,500)