The functions f (x) and g (x) are described below: f (x) = 7x + 9 g (x) = 7x - 4 The graph of g (x) is obtained by shifting down the graph of f (x) by ___ units.

A.) 13

B.) 9

Correct Answer:

Option A

Solution:

f (x) = 7x + 9

g (x) = 7x - 4

We can re-write g (x) as:

g (x) = 7x + 9 - 13

Since 7x+9 is equal to f (x), we can write:

g (x) = f (x) - 13

This relation shows that g (x) is obtained by shifting f (x) 13 units vertically down. So the correct answer is option A.