Решение:
а) $2x = \frac{1}{2}$,
$x = \frac{1}{2} : 2 = \frac{1}{2} * \frac{1}{2} = \frac{1}{4};$
б) $3x = -\frac{1}{4}$,
$x = -\frac{1}{4} : 3 = -\frac{1}{4} * \frac{1}{3} = -\frac{1}{12};$
в) $-2x = \frac{1}{4}$,
$x = \frac{1}{4} : (-2) = \frac{1}{4} * (-\frac{1}{2}) = -\frac{1}{8};$
г) $\frac{1}{2}x = 3$,
$x = 3 : \frac{1}{2} = 3 * 2 = 6;$
д) $\frac{3}{4}x = 1$,
$x = 1 : \frac{3}{4} = 1 * \frac{4}{3} = \frac{4}{3} = 1\frac{1}{3};$
е) $-\frac{1}{3}x = -3$,
$x = -3 : -\frac{1}{3} = 3 * \frac{3}{1} = \frac{9}{1} = 9;$
ж) $-\frac{2}{7}x = 0$,
$x = 0 : -\frac{2}{7} = 0;$
з) $-4x = \frac{8}{25}$,
$x = \frac{8}{25} : -4 = \frac{8}{25} * -\frac{1}{4} = -\frac{2 * 1}{25 * 1} = -\frac{2}{25};$
и) $2x = 1\frac{1}{3}$,
$x = 1\frac{1}{3} : 2 = \frac{4}{3} * \frac{1}{2} = \frac{2 * 1}{3 * 1} = \frac{2}{3}.$
Ответ:
а) $\frac{1}{4};$
б) $-\frac{1}{12};$
в) $-\frac{1}{8};$
г) $6;$
д) $1\frac{1}{3};$
е) $9;$
ж) $0;$
з) $-\frac{2}{25};$
и) $\frac{2}{3}.$