Раскройте скобки:

\(\displaystyle -3 \cdot (a-b\,)=\)[?||-][ ][?|+|-][ ]

\(\displaystyle -(x-y\,)=\)[?||-][ ][?|+|-][ ]

\(\displaystyle -a\cdot (b-c\,)=\)[?||-][ ] [?|+|-][ ]