solve the system using gaussian elimination.

[ochocki]

x + 4y -z = 3
x + 5y -2z =5
3x + 12y -3z =9

I have done this and I think i'm sure that I am right, I get:

x=-3z-5
y=z+2


my problem is with z, it cancels out, what exactly do I write in order to show this?

 

[stapel]

what exactly do I write in order to show this?

Continue on with the solution. You'll get something of the form "x = (something with a constant and a z-term), y = (something else with a constant and a z-term)". Then use whatever your book showed for "parametrized solutions". (There will be an example where they used a variable, often s, t, or a, in their solution.)

Eliz.