Question

What is the effect on the graph of the function f(x) = 5xl when f(x) is changed to f(x – 5)?

Answer 1

A change to the inside of the function notation is always a left/right or horizontal change to the graph.

Answer: A

Subtracting 5 actually shifts the graph to the right by 5 units.  It's counter-intuitive and there are many ways to explain why it's the opposite of what you think it'd do, but it is a shift to the right by 5 units.

PS

A change outside the f(x) notation is an up/down or vertical change to the graph.