6. =7
[tex]( - 2) \div 9 \\ - 2 + 9 \\ = 7[/tex]
7. =19
[tex]16 - ( - 3) \\ 16 + 3 \\ = 19[/tex]
8. =22
[tex] - 11 \times ( - 2) \\ 11 \times 2 \\ 22[/tex]
9. =15
[tex]20 + ( - 5) \\ 20 - 5 \\ = 15[/tex]
10. =-27
[tex] - 18 \: - 9 \\ - (18 + 9) \\ - 27[/tex]