Question

Daca x+y=1.000 si x-y=868 afla valoarea lui x si y si apoi 2×x-3×y

Answer 1

x+y=1000
x-y=868 =>x=868+y
868+y+y=1000
2y=1000-868
2y=132
y=66
x=868+y => x=868+66 => x=934
2*x-3*y= 2*934-3*66=1868-198=1670

Answer 2

x=y+868
y+y+868=1000
yx2=1000-868
yx2= 132
y=132:2
y= 66 ( al doilea numar)
66+868=934 ( primul numar)
 
2x934- 3x66= 1868-178= 1690 (  rezultatul)
proba: 934+ 66= 1000
          934- 66= 868