A set of linear equations is:
[7y - 4x = 6]
[2x - 5y + 6z = 12]
[z = 4]
Solve for (x) and (y).
a) (x = 9) and (y = 6)
b) (x = -19) and (y = -10)
c) (x = 2.6) and (y = 3)
d) (x = -3.25) and (y = -1.1)