Answer:
The answer is -20, 10, and 30.
Step-by-step explanation:
x + y + z = 20
x = y + z
z = 3x
substitute z = 3x
x = y + 3z
-2x = y
substitute z = 3x and y = -2x
x + (-2x) + 3x = 20
2x = 20
x = 10
z = 3x = 30
y = -2x = -20
Now let's check the answer.
x + y + z = 10 -20 + 30 = 20
