Respuesta :

The exponential function has the form:

y= A (B)^x

When x = 0 , y= 4 So:

4 = A (B)^0

4= A

A= 4

So far we have:

y = 4 (B)^x

When x= 1 ,y= 12

12 = 4 (B)^1

12 = 4 B

12/4= B

B= 3

Equation:

y= 4 (3)^x