351 + x = 479
x = 479 − 351
x = 128
$\snippet{name: op_column, sign: '-', x: 479, y: 351, z: 128}$
Проверка:
$\snippet{name: op_column, sign: '+', x: 351, y: 128, z: 479}$
 
x − 521 = 213
x = 213 + 521
x = 734
$\snippet{name: op_column, sign: '+', x: 213, y: 521, z: 734}$
Проверка:
$\snippet{name: op_column, sign: '-', x: 734, y: 521, z: 213}$
 
875 − x = 105
x = 875 − 105
x = 770
$\snippet{name: op_column, sign: '-', x: 875, y: 105, z: 770}$
Проверка:
$\snippet{name: op_column, sign: '-', x: 875, y: 770, z: 105}$