An exponential function y = abx + k passes through (3, 7.5) and (4, 6.25). It also has an asymptote at y = 5. Homework Help ✎
Find the equation of the function.
If the equation also passes through (8, w), what is the value of w?
Substitute 5 for k and then use the points to write a system of equations.
Rewrite each equation by subtracting 5 from both sides.
Solve the first equation for a.
Substitute for a in the second equation.
Solve for b.
k = 5
7.5 = ab3 + 5
6.25 = ab4 + 5
ab3 = 2.5
ab4 = 1.25
a = 20
Substitute 8 for x and w for y.