If the solution of the system of equations ax-by-2z = 13 ax + 2Y + CZ = - 2 about X, y and Z is x = 3, y = - 1, z = - 2, cx-4y + BZ = 31, the value adding process of a, B and C is obtained

If the solution of the system of equations ax-by-2z = 13 ax + 2Y + CZ = - 2 about X, y and Z is x = 3, y = - 1, z = - 2, cx-4y + BZ = 31, the value adding process of a, B and C is obtained

By substituting x = 3, y = - 1, z = - 2 into the equations, we get the following results
3A+B+4=13
3A-2-2C=-2
3C+4-2B=31
Simplification:
3A+B=9 (1)
3A-2C=0 (2)
3C-2B=27 (3)
The solution is: a = 30 / 7, B = - 27 / 7, C = 45 / 7