k3*x7 - k2*x1*x2 
k4 - k5*x2 + k3*x7 - k2*x1*x2 
k6*x4*x5 - k7*x3*x7 
k7*x3*x7 - k6*x4*x5 
k9*x6 - k6*x4*x5 
k7*x3*x7 - k9*x6 
k2*x1*x2 - k8*x7 - k3*x7 
x3 - k10 + x4 
x3 - k11 + x5 + x6 
