12-(     )=8

(     )-4=10

(     )-4=15

20-(     )=19

(     )-18=0

(     )-17=3

(     )-11=2

(     )-9=2

(     )-9=3

16-(     )=11

15-(     )=4

15-(     )=11

(     )-16=0

(     )-10=5

17-(     )=1

13-(     )=5

(     )-10=4

(     )-10=1

(     )-5=6

(     )-10=5

17-(     )=16

(     )-1=15

18-(     )=8

19-(     )=7

(     )-9=3

12-(     )=6

(     )-8=4

(     )-10=2

(     )-4=8

(     )-7=12

17-(     )=17

(     )-11=9

18-(     )=4

(     )-0=11

16-(     )=9

15-(     )=2

(     )-15=4

(     )-3=8

11-(     )=5

19-(     )=2

18-(     )=10

16-(     )=2

(     )-7=4

15-(     )=14

20-(     )=9

18-(     )=18

20-(     )=19

(     )-6=9

11-(     )=3

(     )-7=10