42-...+8=43, ...+1-8=51, ...+6-40=23, 75+4- ...=63, 71 -...+5=76

Question

42-...+8=43, ...+1-8=51, ...+6-40=23, 75+4- ...=63, 71 -...+5=76

Answer 1

42 - х + 8 = 43
-х = -42 - 8 + 43
-х = -7
 х = 7
Проверка: 42 - 7 + 8 = 43;  35 + 8 = 43;  43 = 43
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х + 1 - 8 = 51
х = -1 + 8 + 51
х = 58
Проверка: 58 + 1 - 8 = 51;    51 = 51
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х + 6 - 40 = 23
х = 23 - 6 + 40
х = 57
Проверка:
57 + 6 - 40 = 23;  63 - 40 = 23;      23=23
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75 + 4 - х = 63
79 - х = 63
х = 79 - 63
х = 16
Проверка:75 + 4 - 16 = 63;    79 - 16 = 63;    63 = 63
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71 - х + 5 = 76
-х = 76 - 71 - 5
 х = 0
Проверка:  71 - 0 + 5 = 76;    76 = 76