solve by elimintation
8x -9y = 24.5
7y -2x = -8.5

1. Try to get a variable in the second equation similar to one variable in the first equation.
2. Add or subtract one equation with/from each other.
3. You should now have only one variable.
4. Solve for that variable, and use it to get the other variable.

What do you come up with? :)