Question

Daca X+Y= 1.000 si X-Y= 868 , afla valoarea lui X si Y si apoi calculeaza 2×X-3×Y.

Answer 1

x+y=1000
x-y=868
le adunam
x+x+y-y=1000+868
2x=1868
x=1868:2
x=934
y=1000-934=66
2x-3y=2*934-3*66=1868-198=1670

Answer 2

$x+y=1000 \\ x-y=868 \\ x+x+y-y=1000+868 \\ 2x=1868 \\ x=1868:2 \\ x=\boxed{934} \\ y=1000-934 \\ y=\boxed{66} \\ 2x-3y=934*2-66*3\to1868-198=1670$