Răspuns :
Notez cu x numarul
x* (-2)= x-9
-2x=x-9
-2x-x= -9
-3x= -9 | *(-1)
x=3
Proba 3*(-2)=3-9
-6=- 6 (adevarat)
x* (-2)= x-9
-2x=x-9
-2x-x= -9
-3x= -9 | *(-1)
x=3
Proba 3*(-2)=3-9
-6=- 6 (adevarat)