a-886=2765⇒a=2765+886=3651(a) ,b=886-c acum inlocuim:3651-886-c-c=2765 ,2c=3651-2764-886⇒2c=o⇒c=2×o⇒c=0 , inlocuim iar ca sa aflam b: , b-0=886⇒b=886+o⇒b=886. facem verificarea: a-b-c=2765 , 3651-886-0=2765. incepem subiectul (2): a-b=348621⇒a=348621+8743⇒a=357364 , 357364-b=348621⇒b=357364-348621⇒b=8743 . facem verificarea: 357364-8743=348621 . al treilea exercitiu: 644+c+c=1614⇒2c=1614-644⇒2c=970⇒c=970÷2⇒c=485 ,a+b-c=644 , a+b-485=644, a+b=644-485 , a+b=1129⇒a=1129-b , 1129-b+b+485=1614 ,deci (b) este 0 , a+0+485=1614⇒a=1614-485⇒a=1129 .facem verificarile: a+b+c=1614 , 1129+0+485=1614 . a+b-c=644 , 1129+0-485=644 .
