I believe that the original poster is asking a question about Wolfram Alpha.

If I understand correctly you want Wolfram alpha to divide the entire quantity 3r+6 by 9 rather than just dividing the 6 by 9, correct? And similarly for the expression on the right hand side? So do you want

3r+6/9=4r-24/4

or

(3r+6)/9=(4r-24)/4

Either way, to solve these in Wolfram Alpha just ask (for the second case as an example)

Solve  (3r+6)/9=(4r-24)/4 for r

Then, for the steps to the solution click on "Step-by-step solution" (though this functionality requires a Wolfram Alpha Pro subscription)

Take a look here:

http://wolfr.am/1oDoZCV

Hi Susan,

you could use the Solve[] function to solve these equation:

Solve[(3 r + 6)/9 == (4 r - 24)/4, r]

And if you want to see the step by step solution, you can type in:

==Solve[(3 r + 6)/9 == (4 r - 24)/4, r]

The two equals at the beginning of the line, will start the Wolfram|Alpha mode. So you need an internet connection. I hope it helps!