with(LinearAlgebra): B:=<<-1,1,2,2>|<-1,2,1,2>|<-1,2,2,1>|<0,1,0,0>|<0,0,1,0>|<0,0,0,1>|<0,20,20,20>>;

LUknTWF0cml4RzYkJSpwcm90ZWN0ZWRHSShfc3lzbGliRzYiNiMvSSQlaWRHRiciNUlhWkljcyQpb1c9

B1:=RowOperation(B,3,1/2): B2:=RowOperation(B1,[1,3],1): B3:=RowOperation(B2,[2,3],-1): B4:=RowOperation(B3,[4,3],-2);

LUknTWF0cml4RzYkJSpwcm90ZWN0ZWRHSShfc3lzbGliRzYiNiMvSSQlaWRHRiciNSdHdy9qRFApb1c9

B5:=RowOperation(B4,[1,4],1/2): B6:=RowOperation(B5,[2,4],-3/2): B7:=RowOperation(B6,[3,4],-1/2);

LUknTWF0cml4RzYkJSpwcm90ZWN0ZWRHSShfc3lzbGliRzYiNiMvSSQlaWRHRiciNTFxWkljcyQpb1c9

B8:=RowOperation(B7,2,2/5): B9:=RowOperation(B8,[1,2],1/2): B10:=RowOperation(B9,[3,2],-3/2): B11:=RowOperation(B10,[4,2],1);

LUknTWF0cml4RzYkJSpwcm90ZWN0ZWRHSShfc3lzbGliRzYiNiMvSSQlaWRHRiciNW16WkljcyQpb1c9

C:=<<-3,4,2>|<8,2,3>|<0,1,0>|<0,0,1>|<0,12,6>>;

LUknTWF0cml4RzYkJSpwcm90ZWN0ZWRHSShfc3lzbGliRzYiNiMvSSQlaWRHRiciNTEpeS9qRFApb1c9

C1:=RowOperation(C,2,1/4): C2:=RowOperation(C1,[1,2],3): C3:=RowOperation(C2,[3,2],-2);

LUknTWF0cml4RzYkJSpwcm90ZWN0ZWRHSShfc3lzbGliRzYiNiMvSSQlaWRHRiciNTElei9qRFApb1c9

TTdSMApJQVJUQUJMRV9TQVZFLzE4NDQ2ODgzNzI1NjMwNDc1NDMwWCwlKWFueXRoaW5nRzYiRiVbZ2whIiUhISEjPSIlIighIiIiIiIiIiNGKEYmRihGJ0YoRiZGKEYoRiciIiFGJ0YpRilGKUYpRidGKUYpRilGKUYnRikiIz9GKkYqRiU=TTdSMApJQVJUQUJMRV9TQVZFLzE4NDQ2ODgzNzI1NjMwNDc2Mjg2WCwlKWFueXRoaW5nRzYiRiVbZ2whIiUhISEjPSIlIigiIiFGJiIiIkYmIyEiIiIiIyMiIiRGKiNGJ0YqRidGJkYnRidGKUYmRidGJkYmRi1GKEYtRilGJkYmRiZGJyIjNUYuRi5GJkYlTTdSMApJQVJUQUJMRV9TQVZFLzE4NDQ2ODgzNzI1NjMwNDc3MDA2WCwlKWFueXRoaW5nRzYiRiVbZ2whIiUhISEjPSIlIigiIiFGJiIiIkYmRiZGJkYmRicjISIiIiIjIyIiJkYqIyIiJEYqRilGJkYnRiZGJkYmRidGJ0YpI0YnRiojISIkRipGKEYnIiM1RjJGMkYmRiU=TTdSMApJQVJUQUJMRV9TQVZFLzE4NDQ2ODgzNzI1NjMwNDc3OTY2WCwlKWFueXRoaW5nRzYiRiVbZ2whIiUhISEjPSIlIigiIiFGJiIiIkYmRiZGJkYmRidGJkYnRiZGJiNGJyIiJiMiIiNGKSMhIiRGKUYqRihGKkYqRixGKEYsRipGKiIjNyIiJUYvRi9GJQ==TTdSMApJQVJUQUJMRV9TQVZFLzE4NDQ2ODgzNzI1NjMwNDc4ODA2WCwlKWFueXRoaW5nRzYiRiVbZ2whIiUhISEjMCIkIiYhIiQiIiUiIiMiIilGKCIiJCIiISIiIkYrRitGK0YsRisiIzciIidGJQ==TTdSMApJQVJUQUJMRV9TQVZFLzE4NDQ2ODgzNzI1NjMwNDc5NDA2WCwlKWFueXRoaW5nRzYiRiVbZ2whIiUhISEjMCIkIiYiIiEiIiJGJiMiIz4iIiMjRidGKkYqIyIiJCIiJSNGJ0YuIyEiIkYqRiZGJkYnIiIqRi1GJkYl