## anonymous 3 years ago How do you put this into reduced row echelon form? $$\left[\begin{array}{rrr|r} 3 & -2 & -1 & -8 \\ 5 & 1 & 3 & 23 \\ 4 & 1 & -5 & -18 \end{array}\right]$$

1. anonymous

1) first of all divide with 3 the whole 1st row to get pivot point 1 (all other elements below it should be zero ) . 2) then subtract 4 times of row 1 from 3rd row 3) now subtract 5 times of row one from 2nd row do this and let me know that you get .

2. anonymous

@apple_pi

3. anonymous

ok thanks i'll work on it

4. anonymous

there are steps after this to carried out .. if you want to completely do this first do the above 3 steps and then will let you the further steps..

5. anonymous

So now I have $$\left[\begin{array}{rrr|r} 1 & \frac{-2}{3} & \frac{-1}{3} & \frac{-8}{3} \\ 0 & \frac{13}{3} & \frac{14}{3} & \frac{109}{3} \\ 0 & \frac{11}{3} & \frac{-11}{3} & \frac{-46}{3} \end{array}\right]$$

6. anonymous

@sami-21

7. anonymous

1) ok now multiply the second row with 13/3 to get 1 at the first point 2) then subtract 11/3 times of 2nd row from the third row .

8. anonymous

1) multiply? would that possibly be divide by 13/3?

9. anonymous

@sami-21

10. anonymous

i should have written to multiply with 3/13 ... yes if you divide with 13/3 same .. end result will be 1

11. anonymous

ok.

12. anonymous

Oh, yeah I got it from here. Thanks

13. anonymous

let me give you online interactive tool for free to convert matrix to reduced ech form. go here http://www.math.odu.edu/~bogacki/cgi-bin/lat.cgi select Transforming a matrix to reduced row echelon form (third one in list) then select 3 rows and three columns then enter the left hand part of matrix it will teach you complete steps !