To find: - x , y , z

Given set of lines are : -

x + y - z = 1

3x + y - 2z = 3

x - y - z = - 1

Converting the following equations in matrix form,

AX = B

R₂ – 3R₁

R₃ – R₁

Again converting into equations we get

X + y – z = 1

- 2y + z = 0

- 2y = - 2

Y = 1

- 2 + z = 0

Z = 2

X + 1 - 2 = 1

X = 2

∴