Scaling a row scales the determinant

[Lifprasir]

Homework Statement

http://puu.sh/1rcsO

I got the first one from a simple scaling, but I can not figure out the second one.

Homework Equations

Det(cA) = cDet(A)
Scaling a row scales the determinant
Adding rows/columns to each other does not affect the determinant
Det(A^T) = Det A

The Attempt at a Solution

So, shouldn't I be able to scale http://puu.sh/1rcyZ by -2, and just add row 2 and row 3 by multiples of row 1 ? I actually don't even think this is even close to right because the column 1 and 3 won't resemble each other at all once the row operations are done...

 

[tiny-tim]

Hi Lifprasir!

Hint: what are the gaps between 1,2,3?

what are the gaps between -2,-8,-14?