Dopiš chybějící čísla ve výpočtech.

13 – = 7	11 – 6 =	12 – = 8	+ 8 = 15
+ 9 = 12	8 + = 17	4 + = 13	+ 6 = 15
9 + 3 =	8 + = 13	+ 7 = 12	11 – 5 =
13 – = 8	11 – = 3	17 – 8 =	– 8 = 7
12 – = 5	12 – = 3	17 – 9 =	12 – 4 =