Question

X+3y-2z=1 2x-y+2z=1 -x-4y+6z=2

Answer 1

X + 3y - 2z = 1
-x - 4y + 6z = 2
-------------------add
-y + 4z = 3

x + 3y - 2z = 1....multiply by -2
2x - y + 2z = 1
------------------
-2x - 6y + 4z = -2 (result of multiplying by -2)
2x - y + 2z = 1
-----------------add
-7y + 6z = -1

-y + 4z = 3 .....multiply by -7
-7y + 6z = -1
-----------------
7y - 28z = -21 (result of multiplying by -7)
-7y + 6z = -1
-----------------add
- 22z = -22
z = -22/-22
z = 1 <===

-y + 4z = 3
-y + 4(1) = 3
-y + 4 = 3
-y = 3 - 4
-y = -1
y = 1 <===

x + 3y - 2z = 1
x + 3(1) - 2(1) = 1
x + 3 - 2 = 1
x + 1 = 1
x = 1 - 1
x = 0 <==

so x = 0, y = 1, and z = 1