node, 139 bytes

Result

AC

Duration

572ms

Code [DL]

for(a=(""+require("fs").readFileSync(z=v=0)).split(/\s/);z<9;)v+=(a[z]-=a[z+3])*(z++>5&&a[3+z%3]*a[t=-~z%3]-a[z%3]*a[t+3]);console.log(v/6)

stdin

47 78 96
81 43 37
71 02 93
05 41 60

stdout

49220

stderr

strace