Question

afla numerele x si y stiind ca suma lor este de 2 ori mai mare decat diferenta lor si ca suma adunata cu diferenta este egala cu 600
AJUTOR!

Answer 1

x + y = 2 · ( x - y ) 
( x +y) + ( x  - y ) = 600           ; 2x = 600  ; x = 600 :2 = 300 
300 + y = 2·300 -2·y 
y + 2y = 600 - 300 
3·y = 300 
y =300 :3 =100 

Answer 2

x+y=2(x-y)                                           x+y+x-y=600

x+y-2x+2y=0                                        3y+y+3y-y=600

3y=x                                                     6y=600

                                                             y=600/6=100

       x=3 inmultit cu 100=300           

   R-s: S={300,100}

                                  Verificare:

400=2x200    si         400+200=600                       Corect!