Posted by Terri on Tuesday, February 24, 2009 at 8:52pm.
double the first equation, then add that to the second to get
5x+y = 17
double the second, then add that to the third to get
5x + 4y = 23
now subtract those last two equations to get
3y = 6
y = 2
put that into 5x + y = 17 for
5x = 15
x = 3
now in the first
6 - 2 + z = 3
z = -1
I assumed your second equation had -2z at the end. typo ??
Thanks, yes, typo
I just finished solving it a long way, I solved the first two, then the second two,,etc etc. Your way seems much easier, I did get the same answers, yeah!!!! But, will your way always work?