Answer:
x = 1, y = -2, z = 3.
Step-by-step explanation:
x + 2y + 2z = 3 A
2x -2y - z = 3 B
x - 2z = -5 C
If we add equations A and B we eliminate y:
3x + z = 6 E
Multiply E by 2 :
6x + 2z = 12 F
Adding C and F we get:
7x = 7
x = 1.
Plug this into equaton C:
1 - 2z = -5
-2z = -5 - 1 = -6
z = 3.
Now plugging x = 1 and z = 3 in equation A:
1 + 2y + 2(3) = 3
2y = 3 - 1 - 6 = -4
y = -2.