Răspuns :
x-y=8
2x+3y=21
Metoda Substitutiei
x = 8+y
2(8+y)+3y=21
16+2y+3y=21
5y=5
y=1
x-1=8
x=9
Metoda Reducerii
x-y=8 / *3
2x+3y=21
3x-3y=24
2x+3y=21
5x / 45
x = 9
27-3y=24
-3y=-3
y=1
Spor!
2x+3y=21
Metoda Substitutiei
x = 8+y
2(8+y)+3y=21
16+2y+3y=21
5y=5
y=1
x-1=8
x=9
Metoda Reducerii
x-y=8 / *3
2x+3y=21
3x-3y=24
2x+3y=21
5x / 45
x = 9
27-3y=24
-3y=-3
y=1
Spor!