Раскройте скобки:

\(\displaystyle -7 \cdot (x-b\,)=\)[?||-][ ][?|+|-][ ]

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

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