Posted by Donald on Thursday, July 8, 2010 at 3:59am.
solve by elimiation
2r  9s = 17
9r + 2s = 51

algebra  drwls, Thursday, July 8, 2010 at 5:05am
Multiply your first equation by 9 and the second equation by 2.
18r + 81s = 153
18r + 4s = 102
Next, add those two equations to eliminate the "r" variable.
85s = 255
Take it from there