1453 - x = 783
- x = 783 - 1453
- x = - 670 / -
x = 670
b.
x - 633 = 2941
x = 2941 + 633
x = 3574
c.
x - 67 - 92 = 267
x - 159 = 267
x = 267 + 159
x = 426
d.
542 + x -117 = 638
425 + x = 638
x = 638 - 425
x = 213
e.
( 43 + x ) + ( 537 - 214 )= 975
43 + x + 323 = 975
x + 366 = 975
x = 975 - 366
x = 609
