Solve the following system of equations by using matrices.
x-2y=-6
2y-z=1
x+3z=7
Take a look here:
http://www.wolframalpha.com/input/?i=%7B%7B1,-2,0%7D,%7B0,2,-1%7D,%7B1,0,3%7D%7D*%7B%7Bx%7D,%7By%7D,%7Bz%7D%7D+%3D+%7B%7B-6%7D,%7B1%7D,%7B7%7D%7D
x-2y=-6
2y-z=1
x+3z=7
http://www.wolframalpha.com/input/?i=%7B%7B1,-2,0%7D,%7B0,2,-1%7D,%7B1,0,3%7D%7D*%7B%7Bx%7D,%7By%7D,%7Bz%7D%7D+%3D+%7B%7B-6%7D,%7B1%7D,%7B7%7D%7D