### Home > A2C > Chapter 13 > Lesson 13.1.4 > Problem 13-87

13-87.

An exponential function has an asymptote at *y* = 5 and passes through the points (2, 5.64) and (−1, 15). Find the equation of the function. Homework Help ✎

Since the graph has a horizontal asymptote at *y* = 5 and the *y*-values of the given

points are greater than 5, the graph must have a vertical shift of +5.

Use given points to write a system of equations using the general exponential equation. In this case *y* = *a*(*b*)* ^{x}* + 5.

5.64 = *ab*^{2} + 5

15 = *ab*^{−1} + 5