Question

Linear algebra question?

Answer 1

Anyone want to help me get started? I am pretty sure I can do the rest on my own.

Answer 2

Represent the system in matrix form

Answer 3

Yep, that's what I did.

Answer 4

@Cecily

Answer 5

How do I go on from there?

Answer 6

@zepdrix @Outkast3r09

Answer 7

@dumbcow

Answer 8

take the determinant of the coefficient matrix, and set it equal to zero.

Answer 9

Woah woah!!! We haven't learned what a determinant is yet. :P .

Answer 10

okay.
how about gauss-jordan reduction?

Answer 11

Yeah. We learned that.

Answer 12

i got something easier than gauss-jordan.

multiply equation 2 by (-1), and equation 3 by 2, then add the two equations.

Answer 13

Elimination?

Answer 14

yup.

Answer 15

3y-3z=-a+2 ?

Answer 16

not 3y+3z = -a + 2 ?

Answer 17

Yeah. My mistake.

Answer 18

Allright, what next?

Answer 19

use that equation with equation 1 to eliminate both y and z.

Answer 20

1 sec.

Answer 21

THat dosen't eliminate it. It makes it bigger.

Answer 22

bx + 3y + 3z = a
3y + 3z = 2 - a

subtract.

Answer 23

I used substitution instead. Should till be valid right?

Answer 24

or if you wish to substitute...

Answer 25

that's valid too.

Answer 26

bx + (2-a) =a

bx = 2a - 2