Yes. Why are you "not sure"?
Did you notice this quick way to get z? (NOT important, really...more luck!)
4x-y+2z= 10 
-8x +2y + z= -35 
8x -2y + 4z = 20 *2
I was wondering if anyone could verify my answer to the following:
Determine if the given values are a solution of this system:
I got x=4, y=0 and z=-3
So yes, the given values are a solution of this system.
Is this correct?
I wasn't sure if the value of my variables were placed properly, when I did them in the order listed above, the equations came out true. I was just double checking. Each of my questions are worth 10 points and I really can't afford to miss any if possible. I guess I was more so second guessing myself?