Question

rezolvati in a) x+y=15 x-y=10​

Answer 1

Răspuns:

Metoda 1:

x+y=15

x-y=10

----------(+) (adunam prima ecuatie cu a doua)

2x+0=25=>x=25\2=>x=12.5=>y=2.5

Metoda 2:

x+y=15 (1)

x-y=10=>x=10+y (2)

(1)+(2)=>10+y+y=15=>2y=5=>y=2.5=>x=12.5

Sper ca te-am ajutat :)