You have a typo in your first equation.

Not a real good candidate for substitution, but if you have to.....

Step 1: Solve the first equation for x or y (whichever is easier).

Step 2: Substitute that into your second equation to solve for your 1st variable.

Step 3: Finally, use your answer from Step 2 and substitute into Step 1 to solve for the 2nd variable.

After you fix your typo, I can be more specific.