Need help with matrix algebra, should be simple in theory?

Find the line of intersection of the following planes:

3x +2y +z = -1

2x -y + 4z = 5

To my understanding, in theory this should be a simple augmented matrix that just needs to be row reduced. But no matter how I try to do it, I get the following answer:

x = -9t/7 + 9/7

y = -10t/7 - 17/7

z = t

And the correct answer is supposedly:

x = 9t

y = -10t -1

z = -7t +1

I'm extremely frustrated here, can anyone lend a hand?