Question

elimination matrices / Gaussian elimination

Answer 1

R1 * 2 + R2 => R2

[0 1 3]

R2 * -3 + R3 => R3

[0 0 -22]

Answer 2

im not so sure how you know how to do that though, this is all new to me and im a bit behind.

Answer 3

yes

Answer 4

i see how you made it triangular, but im wondering how to setup the elimination matrices so that it comes out that way when you multiply it.

Answer 5

so we have

U =