a) (y + 4) - (y - 1) = 6y
$$y + 4 - y + 1 = 6y$$
$$5 = 6y$$
$$y = \frac{5}{6}$$
б) 3p - 1 - (p + 3) = 1
$$3p - 1 - p - 3 = 1$$
$$2p - 4 = 1$$
$$2p = 5$$
$$p = \frac{5}{2}$$
$$p = 2,5$$
в) 6x - (7x - 12) = 101
$$6x - 7x + 12 = 101$$
$$-x = 101 - 12$$
$$-x = 89$$
$$x = -89$$
г) 20x = 19 - (3 + 12x)
$$20x = 19 - 3 - 12x$$
$$20x + 12x = 16$$
$$32x = 16$$
$$x = \frac{16}{32}$$
$$x = \frac{1}{2}$$
$$x = 0,5$$
<p><strong>Ответ: а) y = $$\frac{5}{6}$$; б) p = 2,5; в) x = -89; г) x = 0,5.</strong></p>