Question

Solve the following system of equations.

2x – y + z = –3
2x + 2y + 3z = 2
3x – 3y – z = –4

(1, 3, 2)

(–1, 3, 2)

(1, –3, 2)

(1, 3, –2)

Answer 1

if i were you i'll add the first equation and third equation first...

Answer 2

if you've got the choices,check which triplet satisfies the 3 equations

Answer 3

that's too long of a process :C and no fun too >:))

Answer 4

So you have a couple choices. You can check the possible answers. If you do that, i'd recommend using the second equation first..
You can do elimination.
You can use Cramer's rule.

2 -1 1 | -3
2 2 3 | 2
3 -3 -1 | 4

Let's do elimination.

Answer 5

taking too long, try eliminating z first
I add eqn 1 to eqn 3, also -3 times eqn 1 plus eqn 2, I get

5x - 4y = -7
-4x + 5y = 11

Peeking at the answers, x = 1, y = 3 works.
Try in eqn 1 I get z = -2
Check my work, I could have made a mistake!