Răspuns:
15.
2x + 37 = 59 => 2x = 22 => x = 11
16.
3x - 52 : 2 = 1 => 3x = 26 + 1 => 3x = 27 => x = 9
17.
(x + 2) : 24 = 5 => x + 2 = 120 => x = 118
18.
(x - 3) × 5 + 25 = 100 => (x - 3) × 5 = 75 => x - 3 = 15 => x = 18