If you add the two equations in the middle together, you'd end up with
-3y = 15
And divide both sides by -3 and you'd have
y = -5
Since there's only one solution with a y-value of -5, it must be the first option, (-19/2, -5).
You can confirm this is correct by substituting in -19/2 for x and -5 for y in both equations.