powershell, 157 bytes

Result

WA

Duration

1324ms

Code [DL]

$s=$Input.Split()
3..11|ForEach{$s[$_]-=$s[$_%3]}
echo(($s[11]*($s[7]*$s[3]-$s[4]*$s[6])+$s[10]*($s[8]*$s[3]-$s[5]*$s[6])+$s[9]*($s[4]*$s[8]-$s[7]*$s[5]))/6)

stdin

53 08 56
29 15 22
43 34 74
50 65 47

stdout

-7008

stderr

strace