Addition and takeaway

1 + 1 =  2                1 - 2  = 0

2 + 2  = 4                3 - 2  = 1

3 + 3  = 6               5  - 1 = 4

4 + 4 = 8                10 - 8 =   2

5 + 5 = 10              11 - 5 =   6

6 + 6  = 12              7 - 4  =   3

7 + 7 = 14                3 - 2 =  1

8 + 8 = 16                 2 - 0 =  2

9 + 9 = 18                 5 - 4 =  1

10 + 10 = 20               6 - 5 =  1