Question

X+3y−z=2
4x+2y+5z=1
3x+z=12

Answer 1

• x=5, y= -2, z= -3

Explanation:

Given system of equations

• x+3y−z=2 (1)
• 4x+2y+5z=1 (2)
• 3x+z=12 (3)

Solution

3*(2) - 2*(1)

• 10x + 17z = -1 (4)

17*(3) - (4)

• 51x - 10x + 17z - 17z = 12*17 - (-1)
• 41x = 205
• x = 5
• 5*3 + z = 12 ⇒ z = -3
• 5 + 3y -(-3) = 2 ⇒ 3y = -6 ⇒ y = -2