Question

5. (04.07)

Which of the following exponential functions goes through the points (1, 12) and (2, 36)? (2 points)
f(x) = 3(4)^x
f(x) = 4(3)^-x
f(x) = 3(4)^-x
f(x) = 4(3)^x​

Answer 1

f(x) = 4(3)^x​

Explanation:

Answer 2

D) f(x) = 4(3)^x​

Explanation:

Plug y in for f(x) and plug in the points so if they are both true in one equation then it is correct.

A)

y = 3(4)^x

36 = 3(4)^2

36 = 3(16)

This is already incorrect

B)

y = 4(3)^-x

36 = 4(3)^-2

36 = 4(1/16)

36 ≠ 1/4

This is incorrect

I'm going to skip C because I believe D is correct:

D)

y = 4(3)^x​

36 = 4(3)^2

36 = 4(9)

36 = 36

Now we plug in the other points

y = 4(3)^x​

12 = 4(3)^1

12 = 4(3)

12 = 12