Question

I need help!, check my answer
use cramer's Rule 3 x3
' -1 1 1 '
' -9 5 3 '
' 5 -2 -1 '
' '
the key is -2, but my answer is 0,thank you in advance

Answer 1

i'll try though y memory of this is poor
do u mean the determinant?

Answer 2

like -1 * (5*-1 - (-2*3)) etc ?

Answer 3

my answer keep 0 but the key is -2 I check with alpha,myalgebra answer still -2

Answer 4

http://www.wolframalpha.com/input/?i=3x%2By%2Bz%3D-1%2C-6x%2B5y%2B3z%3D-9%2C9x-2y-z%3D5http://www.mathway.com/answer.aspx?p=calg?p=3x+y+zSMB01-1,-6x+5y+3zSMB01-9,9x-2y-zSMB015?p=700?p=?p=?p=?p=?p=0?p=?p=0?p=?p=
I solve y , z is correct only x have a problem,I don't see I do wrong

Answer 5

isn't it -1[(5*-1)-(-2*3)] - 1[((-9*-1)- (5*3)] +

but i'm not sure about the sign pattern

is it

+ - +
- + -
+ - +

?

Answer 6

ahha . I see thank you for remind me , I forgot change second equation side, thank,thank,thank,...........

Answer 7

i'll go and check my textbook

Answer 8

it ok I know now

Answer 9

good

Answer 10

thank you very much