Question 259755
Hello, 
First off we want to see if we can eliminate one of the variables. 
7r-4s=33
4r+7s=56
Let's go for getting rid of "s". To do this we need to multiply the first equation by 7 and the second equation by 4 so it would turn out like this:
49r-28s=231
16r+28s=224
Now we can add both of these to be:
65r=455 Divide each side by 65 to result in:
r=7
Now we can plug 7 into either original equation to find "s".
49-4s=33 Subtract 49 from both sides to be:
-4s=-16 Now divide -4 into both sides to give us:
s=4 
You can check to see if this is right by plugging s=4 and r=7 into both equations. 
Make sense?
RJ
Check out a new book I wrote at:
www.math-unlock.com