2) 3(2,5-2x) = 13,5-14x;

Решение:

1. \( 3(2,5-2x) = 13,5-14x \)
2. \( 7,5 - 6x = 13,5 - 14x \)
3. \( 14x - 6x = 13,5 - 7,5 \)
4. \( 8x = 6 \)
5. \( x = \frac{6}{8} \)
6. \( x = \frac{3}{4} \)

Ответ: x = 3/4