Question

2x + 2y+z = 7; 2x - y +2z = 4 ; x+y - 2z = -1 by Cramer rule

Answer 1

∴ We can apply Cramer’s Rule and the system is consistent and it has unique solution.

= 1(– 8 + 2) – 7(– 4 – 2) + 1(– 2 – 4)

= 1(– 6) – 7(– 6) + 1(– 6)

= – 6 + 42 – 6

= 30

∴ The Solution is (x, y, z) = (1, 2, 2)