SOLUTION: Hi! I'm stumped on this last question on my homework. It's substitution and for some reason i can't figure it out and i kepe getting different answers for the variables. Could you

Algebra.Com
Question 104174: Hi! I'm stumped on this last question on my homework. It's substitution and for some reason i can't figure it out and i kepe getting different answers for the variables. Could you help me please? I don't think i can figure this one out.
x+y+3z=-4
-x-y-2z=5
2x-z=-3
thanks!!!

Answer by scott8148(6628)   (Show Source): You can put this solution on YOUR website!
solving for y in the first equation gives y=-4-x-3z

substituting into the second equation gives -x-(-4-x-3z)-2z=5 ... -x+4+x+3z-2z=5 ... 4+z=5 ... z=1

substituting into the third equation gives 2x-(1)=-3 ... 2x=-2 ... x=-1

substituting back to the first equation gives -1+y+3(1)=-4 ... y+2=-4 ... y=-6

RELATED QUESTIONS

Thanks in advance - this is the last question on my homework and I can't figure it out.... (answered by funmath)
I am studing the substitution Method.. and for some reason i can not seem to figure out... (answered by xcentaur)
My teacher handed us a worksheet on algabraic proofs and told us to do it for homework. I (answered by rothauserc)
6x+2/z=7/y, solve for z How do i get z on one side and everything else on the other... (answered by ewatrrr)
PLEASE help me with this.... one side of a triangle has a length of 5x-2. a longer side... (answered by bucky)
Hi I am completely stumped on this one i can not for the life of me figure it out...I... (answered by reviewermath)
I need help this is the last question on my homework and i have been siting here for 30... (answered by jim_thompson5910)
I have worked out most of my questions tonight and this one is just stumping me for some... (answered by gsmani_iyer)
Hello! I’m really stumped on this. The question says to consider the infinite geometric (answered by math_helper)