1) (x-274) + 356=481

2) 478 - (256+x) = 143

3) 659 - (345-x) = 427

4) 791 - (x-298) = 683

(Х+458) - 156=348 Х+458-156=348 Х = 348 - 458 + 156 х = 46 (х-356) - 245=147 х-356-245=147 х = 147 + 356 + 245 х = 748 (х-274) + 356=481 х-274 + 356=481 х = 481 + 274 - 356 х = 399 478 - (256+х) = 143 478-256-х=143 - х = 143 - 478 + 256 х = 79 659 - (345-х) = 427 659-345+х=427 х = 427 - 659 + 345 х = 113 791 - (х-298) = 683 791-х+298=683 - х = 683 - 791 - 298 х = 406

1) (x-274) + 356=481

(x-274) = 481-356

(x-274) = 125

x=125+274

x=399

2) 478 - (256+x) = 143

(256+x) = 478-143

(256+x) = 335

x=335-256

x=79

3) 659 - (345-x) = 427

(345-x) = 659-427

(345-x) = 232

x=345-232

x=113

4) 791 - (x-298) = 683

(x-298) = 791-683

(x-298) = 108

x=108+298

x=406