What is the effect on the graph of the parent function f(x) = x when f(x) is replaced with 4f(x)? a) same slope, same y-intercept b) same slope, different y-intercept c) different slope, same y-intercept d) different slope, different y-intercept

Remark
The way this is written I would assume that it means 4*f(x) = x. That may not be entirely the correct assumption to be made. 

Step One
Replace f(x) by 4f(x)
4*f(x) = x  

Step two
Divide both steps by 4
f(x) = x/4 or (1/4)x
The slope is now 1/4

Discussion
A is incorrect.
The slope has been changed. 

B is incorrect
The slope has been changed to 1/4 and the y intercept is still 0

C looks to be the right answer.

D The y intercept is still zero. 

Comment
The question is a little hard to interpret. I've read it literally. That means that I have taken the question to mean that only f(x) was altered. If however, the right side was multiplied by 4 as well (as should be done), then the answer is A same slope same intercept. That's because the 4s on the left and right cancel, and the original equation results. I'm going to pick C but don't be surprised if it is A

C <<<<<answer