# Variables in Average Rate of Change?

• Jan 27th 2010, 09:28 PM
nox16
Variables in Average Rate of Change?
(5(x + h) - 4) - (5(x) - 4)/x + h - x

What do I do after that? Do I continue with this?

(5(x + h) - 4) - 5(x) + 4/h
after..

5x + 5h - 4 - 5(x) + 4/h

5h/h

http://i49.tinypic.com/14iimwo.jpg
• Jan 27th 2010, 09:32 PM
VonNemo19
What you have done is correct. To make sure, what is the rate of change of $y=5x-4$? Its the slope! 5!!!!!!!
• Jan 27th 2010, 09:35 PM
fishcake
Quote:

Originally Posted by nox16
(5(x + h) - 4) - (5(x) - 4)/x + h - x

What do I do after that? Do I continue with this?

(5(x + h) - 4) - 5(x) + 4/h
after..

5x + 5h - 4 - 5(x) + 4/h

5h/h

Yes, I think you got the answer (5). (Happy)
• Jan 27th 2010, 09:51 PM
nox16
Thank you so much for confirming me with that. The answer in the back is 5, but I wasn't not quite sure if the way I was doing is correct. Thanks for help me out guys!