Hey guys, I'm having a lot of trouble with this problem:
5x + 4y = 29
y + z - w = -2
5x + z = 23
y - z + w = 4
Yeah, I don't even know where to start on this one, so any kind of help would be greatly appreciated.
for example, note that we can solve for y by adding the second and fourth equations
another way would be to continue like nothing happened, and try to add/subtract other sets of equations to eliminate other variables. sometimes you won't be left with just one variable as you were with y. but you can add/subtract the new equations you form to eliminate other variables until you are left with one.