Y = -1.4
The simplest way to find the answer is to cancel out the x - values. Set both equations equal to zero.
10x + 8y + 24 = 0
5x - 6y - 2 = 0
Multiple the second equation by -2 so the x terms cancel out when you add them together.
10x + 8y + 24 = 0
-10x + 12y + 4 = 0
20y + 28 = 0
20y = -28
Y = -1.4