Rezolvati prin metoda substitutiei sitemele:
2x+y= -7
3x-4y= -5

x-2y= -8
3x+4y= -4

DAU COROANA!


Răspuns :

y=-7-2x

y=-7-2x

3x-4(-7-2x) = -5

y=-7-2x

3x+28+8x = -5 /-28

y=-7-2x

11x = -33 / : 11

y=-7-2x

x = -3

x=-3

y=-7-2×-3

x=-3

y=-7+6

x=-3

y=-1

S = {(-3;-1)}