[ Eq(Derivative(x1, t), (-1)*k1*(k2*x1*x2 - k3*x7)/k1),
  Eq(Derivative(x2, t), ((-1)*k1*(k2*x1*x2 - k3*x7) + 1*k1*k4 + (-1)*k1*k5*x2)/k1),
  Eq(Derivative(x3, t), (1*k1*k6*x5*x4 + (-1)*k1*k7*x7*x3)/k1),
  Eq(Derivative(x4, t), ((-1)*k1*k6*x5*x4 + 1*k1*k7*x7*x3)/k1),
  Eq(Derivative(x5, t), ((-1)*k1*k6*x5*x4 + 1*k1*k9*x6)/k1),
  Eq(Derivative(x6, t), (1*k1*k7*x7*x3 + (-1)*k1*k9*x6)/k1),
  Eq(Derivative(x7, t), (1*k1*(k2*x1*x2 - k3*x7) + (-1)*k1*k8*x7)/k1) ]