Răspuns:
900 + 2 - a × 100 = 302
902 - 100a = 302
-100a = 302-902
-100a = -600
a = 6
a × ( 57- 13 ×4 ) = 40
a × 5 = 40
a = 40 : 5
a = 8
(m × 2 - 40 ) : 23 = 12
(2m - 40): 23 = 12
(2x - 40) / 23 = 12
2x - 40 = 276
2x = 276 + 40
2x = 316
x = 158
(m - 416: 4 + 2 ) × 5 = 1980
(m - 102) × 5 = 1980
5x - 510 = 1980
5x = 1980 + 510
5x = 2490
x = 2490 : 5
x = 498
