Answer:
x = 1, y = -1, z = 3
Explanation:
x - 2y + 2z = 9
y + 2z = 5
z = 3
According to the last equation, z is equal to 3 so we can plug that in and our new 2 equations will be:
x - 2y + 6 = 9
y + 6 = 5
We can subtract 6 from both sides of the second equation to end up with:
y = -1
Now plugging this into the first equation, we have:
x + 2 + 6 = 9
x + 8 = 9
Subtract 8 from both sides
x = 1