x12, x11, x10, x9, x8, x7, x6, x5, x4, x3, x2, x1, 
x12*x3-x7*x8
-x10*x6+x11*x5
x1*x8-x1*x9+x3*x9-x4*x8
x1*x11-x1*x12-x11*x7+x12*x6
-x10*x2+x10*x3+x2*x8-x5*x8
-x11*x2+x11*x4+x2*x9-x6*x9
x10*x4-x10*x7-x12*x4+x12*x5-x5*x9+x7*x9
