Question

x+y+z=7
2x+y-z=0
2x-3y+z=0
solve the system.

Answer 1

You can solve this by using Cramer's Rule.

You set the equation up into a 3x3 Matrix

1 1 1
2 1 -1
2 -3 1

You find the determninant of this equation, it is -14.
Then you set up the other 3 matrices with the answers in the x,y,and z columns.

Dx=-14
Dy=-28
Dz=-56

You then divide these numbers by -14.

The solution is(1,2,4)