1) 4 + 9 = 13
9 + 4 = 13
13 - 9 = 4
13 - 4 = 9
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2) 17 - 6 = 11
17 - 11 = 6
11 + 6 = 17
6 + 11 = 17
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3) 12 + 8 = 20
8 + 12 = 20
20 - 12 = 8
20 - 8 = 12
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4) 18 - 3 = 15
18 - 15 = 3
3 + 15 = 18
15 + 3 = 18
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Задание № 2.
5 + 9 = 14 6 + 8 = 14 4 + 8 = 12 6 + 7 = 13
14 - 9 = 5 14 - 8 = 6 8 + 4 = 12 13 - 7 = 6
14 - 5 = 9 8 + 6 = 14 12 - 8 = 4 13 - 6 = 7
9 + 5 = 14 14 - 6 = 8 12 - 4 = 8 7 + 6 = 13
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