Question

X + X + X = 30
X + Y + Y = 18
Y – Z = 2
Z + X + Y = ???

Answer 1

Answer: 16

Explanation:

1. For the first equation, we see that 3x=30. Divide both sides by 3, we see that x=10.

2. If we substitute 10 for x and add that to 2y, we see that 2y+10=18. If we subtract 10 from each side, we see that 2y=8. If we divide each side by two, y=4.

3. If we substitute 4 for y, we see that 4-z=2. 4-2 is 2, so we know that z is 2.

4. If we add all the values we've found, we see that 4+2+10=16.