I guess you mean simultaneous equations. There are three methods of solving these equations: graphing if the variables are x and y (though this is only an approximate method and should be avoided...
Lets say that the equation is: 2+3x+2x=22 2+5x=22 Combine Like Terms. 2-2+5x=22-2 Subtract 2 from each side. 5x=20 Simplify. 5x/5=20/5 Divide 5 on each side. x=4 Simplify. Check... 2+3x+2x=22 x=4...