Answer:
-3
Step-by-step explanation:
Since x=1, we can simplify the equation to 9+7y=-12.
To find the value of 7y, we first have to find what is missing.
-12-9=-21, so 7y has to be equal to -21. -21/7 equals -3, so y=-3.
(2x - 3y + 5z) - (-4x - y + 8z)
= 2x - 3y + 5z + 4x + y - 8z
= 6x - 2y - 3z
In short, Your Answer would be Option D
Hope this helps!
No there is no variability cause the answers will always be the same
