Which method is better is really a matter of opinion. I prefer to do elimination when I can because seems like less steps but that x is alone and can be substituted easily as well.
* elimination method, multiply entire bottom equation by -4 and added equations together
4x + 2y = -2
-4(x - 3y = 24)
--------------------
0 + 14y = -98
y = -7
then
x - 3(-7) = 24
x + 21 = 24
x = 3
