Question

1 2 -1 | -1
2 5 -1 | -4
-3 -9 -5 | -5

a)R_2=-2(r1)+(r2)
b)R_3=3(r1)+(r3)
c)R_3=3(r2)+(r3)

I got...

1 2 -1 | -1
0 1 1 | -2
0 0 -5 | ?

I cannot figure out the last one ;/
0 0 -5
0 0

Answer 1

ignore those nmbers at the end please

Answer 2

i think there is a mistake at row 3 check it out ?

Answer 3

its all right but i cant get the last one.

Answer 4

w8 i m mistaken hold on

Answer 5

or did u get correct till here (after 2 steps you mentioned)
1 2 -1 | 1
0 1 1 |-2
0 -3 -8|-8

Answer 6

yeah

Answer 7

3 R2+R3 will give you 3(-2)+-8 = -6-8 = -14 on the right.