What's up wonder community of math wizards. I was hoping you could check a problem for me. For every step I need to pick which numbered law from the list was used. HERE IS THE LIST.

Given =$\displaystyle \overline{(A\overline{BC}+\overline{AC})(\overline {A+B)}}$

19 ===$\displaystyle \overline{A\overline{BC}+\overline{AC}}+\overline{ \overline{A}+\overline{B}}$

20 ===$\displaystyle \overline{A\overline{BC}+\overline{AC}}+\overline{ \overline{AB}}$

9 ====$\displaystyle \overline{A\overline{BC}+\overline{AC}}+AB$

20 ===$\displaystyle \overline{(A\overline{BC}})\overline{(\overline{AC )}}+AB$

9 ====$\displaystyle \overline{(A\overline{BC}})(AC)+AB$

19 ===$\displaystyle (\overline {A}+\overline{\overline{BC}})(AC)+AB$

9 ====$\displaystyle (\overline{A}+BC)(AC)+AB$

15 ===$\displaystyle \overline {A}AC+ABCC+AB$

7 ====$\displaystyle 0\bullet C+ABCC+AB$

3 ====$\displaystyle 0+ABCC+AB$

1 ====$\displaystyle ABCC+AB$

5 ====$\displaystyle ABC+AB$

18 ===$\displaystyle AB$

I think I might of got it right. #15 I'm not feeling good about.