FACE TI MI SISTEMUL ĂSTA VA ROG FRUMOS

3a - b= -9 /×2
9a +2b= -15
6a -2b= -18
9a +2b= -15
----------------- (+) aplic metoda reducerii
15a / = -33 => a= -11/5
3×(-11/5) -b= -9
-33/5 -b= -9
b= -33/5 +9 = -33/5 + 45/5= 12/5