x=raspunsuri corecte
y=raspunsuri gresite
[tex] \left \{ {{x+y=10} \atop {25x-15y=130}} \right.\ \textless \ =\ \textgreater \ \left \{ {{25x+25y=250} \atop {25x-15y=130}} \right.\\
Le\ scadem:/40y=120=\ \textgreater \ y=3\ raspunsuri\ gresite.\\
x+3=10=\ \textgreater \ x=7\ raspunsuri\ corecte.[/tex]