Question

For which function does f (14) = 23?

A. f(x) = 1/2x - 20

B. f(x) = 3x - 7

C. f(x) = x +9

D. f(x) = 14x + 23

Answer 1

Answer:

C. $f(x) = x + 9$

Step-by-step explanation:

To find the answer we need to put 14 into each of the functions. When it says $f(14)$  we are basically replacing every value in the function with 14.

So for the first function we can say.

A. $f(14) = \frac{1}{2(14)} - 20$ = $-\frac{559}{28}$

This doesn't equal 23 so we can go to the next function and put in 14.

B. $3(14) - 7 = 35$

C. $14 + 9 = 23$

For C we get $f(14) = 23$ which is what we are looking for so the function is $f(x) = x + 9$.