1) ((х +405) - 613) = 705 - 702
(х + 405) = 613 + 3
х + 405 = 616
х = 616 - 405
х = 211
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2) (283 - ( х - 29)) = 1996 - 1917
283 - х + 29 = 79
- х = - 283 - 29 + 79
-х = -233
х = 233
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3) ((232 - х) + 403) = 735 - 217
(232 - х) = 518 - 403
232 - х = 115
х = 232 - 115
х = 117
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4)((х + 483) + 689 = 1243 - 71
( х + 483) = 1172 - 689
х + 483 = 483
х = 483 - 483
х = 0