What is the rate of increase in this function: y = 15(1.12)^x ?

Answer 1

The general form of an exponential equation is:

y = a·(1+rate)^x

Hence 1.12 = 1 + rate

Solve for the rate. Note that the rate is positive for exponential growth and negative for decay.

Answer 2

The Compound Interest formula is: A = A₀(1 + r)^rt where r is the rate and t is time.

Rewrite the 1.12 in your equation as 1 + .12. The rate is 12%.