You would have to multiply either equation in order to get one of the variables to cancel.
I would multiply the first equation by -5.
-5(3x + 6y = -2)
-15x -30y = 10
15x + 30y = -10
0 + 0 = 0
Since everything cancels and the equation is true, the solution is Infinitely many solutions, or all real numbers.
