ruby, 82 bytes

Result

WA

Duration

504ms

Code [DL]

require'matrix'
x=$<.map{|l|Vector[*l.split.map(&:to_i),1]}
p-Matrix.rows(x).det/6

stdin

16 53 10
30 07 08
69 61 86
23 42 61

stdout

stderr

/volume/CODE:3:in `<main>': undefined method `-' for nil:NilClass (NoMethodError)

strace