## boomerang285 2 years ago Solve the matrix : |1 2 1| 0 | |0 1 0|-2| |0 0 1| 3 |

1. technopanda13

open study is for help not answers :)

2. boomerang285

i know that, I am looking for help in solving this matrix

3. nubeer

i think the person has just stated the question. maybe he needs help solving it

4. nubeer

hmm @boomerang285 just want to know.. familiar with Guass jordan? is it related to it?

5. boomerang285

yes I believe so, I am looking in my textbook, it is just very confusing

6. nubeer

ok and you have to find x, y, and z right?

7. boomerang285

yes

8. nubeer

ok see your matrix.. all the elements below the peincipal diagnol are 0.. so you can apply Guass method.

9. boomerang285

ok

10. nubeer

ok so in guass u make equations like this. just ignore the last column in you question and replace it with x,y ,z|dw:1352480536058:dw|

11. nubeer

1x+2y+z = 0 y = -2 0x+0y+1z = 3 just now solve these equations

12. boomerang285

so the answer is then (1, -2, 3) ? thats what i get

13. nubeer

yes .. that should be the answer.. you have to remmeber you can do like this just when you have all elements under principal diagonal are 0

14. boomerang285

thank you very much, i have a couple questions i need checked, are you willing?

15. nubeer

yeah sure..

16. boomerang285

these ones i have to solve using cramers rule, If you are familiar. x-2y=5 5x-y=-2 The answer for this one that I come up with is (-1, -3)

17. boomerang285

solve with cramers rule 2x-9y=5 3x-3y=11 i come up with (4, 1/3)

18. nubeer

second one is right.

19. nubeer

yup.. both of them are right :)

20. boomerang285

thank you so much!

21. nubeer

you are most welcome