The graph of an exponential model in the form y = a ⋅ bx passes through the points (3, 5) and (4, 10). Which point is also on the graph?

Question

A. (2,0)

B. (2,1)

C. (5,15)

D. (5,20)

Answer 1

First, find a and b from the given points.

y = ab^x

5 = ab³

10 = ab⁴

b = 10/5 = 2

5 = a(2³)

a = 5/8

y = (5/8) 2^x

Test the choices:

x = 2 ⇒ y = 5/2

This rules out (a) and (b).

x = 5 ⇒ y = 20

Choice (d) is good,