Question

Solve the system using the elimination method.

2x+y−z=9
2x+y−z=9

−x+6y+2z=−17
−x+6y+2z=−17

5x+7y+z=4

Answer 1

you have three equation with three variables
\[2x+y-z=9\]
\[-x+6y+2z=-17\]
\[5x+7y+z=4\]

Answer 2

to use elimination method:
multiply the first and third equations by 2

Answer 3

And after that step

Answer 4

or you can just multiply the first one by 3 and add all equations together, you will eliminate the variable z

Answer 5

Eliz: It's not for us to give you the final solution; you need to get involved and find it yourself with guidance from others. What have you done so far?

Answer 6

for more details, you can refer to this pdf