5.544 Решите уравнение: а) (2 - 6) * y - 3/7 = - 3 ; б) 1/4 * y - 1/4 = - 1/4

a) $$(2 - 6) \cdot y - \frac{3}{7} = -3$$

$$-4 \cdot y - \frac{3}{7} = -3$$

$$-4y = -3 + \frac{3}{7}$$

$$-4y = \frac{-3 \cdot 7 + 3}{7}$$

$$-4y = \frac{-21 + 3}{7}$$

$$-4y = -\frac{18}{7}$$

$$y = \frac{18}{7} : 4$$

$$y = \frac{18}{7} \cdot \frac{1}{4}$$

$$y = \frac{18}{28}$$

$$y = \frac{9}{14}$$

Ответ: $$\frac{9}{14}$$

б) $$\frac{1}{4} \cdot y - \frac{1}{4} = -\frac{1}{4}$$

$$\frac{1}{4}y = -\frac{1}{4} + \frac{1}{4}$$

$$\frac{1}{4}y = 0$$

$$y = 0: \frac{1}{4}$$

$$y = 0 \cdot 4$$

$$y = 0$$

Ответ: 0