The answer is that the first one is not the longer one the second one is.
the first one equals 2
the second one equals 5
(2x + 3y = 12) x (-2)
(4x - 3y = 6) x 1
-4x - 6y = -24
4x - 3y = 6
You can cancel out the x values by adding the two equations together.
(-4x + 4x) + (-6y - 3y) = (-24 + 6)
-9y = -18
y = 2
Solve for x now...
4x - 3(2) = 6
4x - 6 = 6
4x = 12
x = 3
Check... (x = 3, y = 2)
2(3) + 3(2) = 12
6 + 6 = 12
12 = 12 <- this works!
4(3) - 3(2) = 6
12 - 6 = 6
6 = 6 <- this works!
H = -0.25 I think don't really know, okay?