solve this system of equations
x+y+z=-2
2x+5y+2z=2
-x+7y-3z=24

Question

hero · Answer

Add the first and third equations together to make it easier

hero · Answer

Than add that result to the middle equation

hero · Answer

Then solve for y

radar · Answer

y=2, x=-1, z=-3   Use elimination method.

radar · Answer

Many ways to approach, but you can solve for y by taking the second equation and subtracting the first equation multiplied by 2.

hero · Answer

Yeah, my approach didn't help much

radar · Answer

2x +5y + 2z = 2
2x +2y + 2z = -4
-----------------
      3y            = 6
y=2

Now you take it from there.

radar · Answer

Hero it did eliminate one of the unknowns, so it was a good start.

radar · Answer

Now substitute for y from what you got with Hero suggestion.
8y-2z=22
16-2z=22
-2z=6
z=-3  Now you are home free.