3. Решите уравнение: a) x + 5 = 7, 12 12' x = 7-5 12 12', x = б) x-4 = 16 15 15', x =+=, x = 13 4 B) 17-x=17', x == x =

3. Решите уравнение:

а) $$ x + \frac{5}{12} = \frac{7}{12} $$,

$$ x = \frac{7}{12} - \frac{5}{12} $$,

$$ x = \frac{7 - 5}{12} $$,

$$ x = \frac{2}{12} $$,

$$ x = \frac{1}{6}. $$

б) $$ x - \frac{4}{15} = \frac{16}{15} $$,

$$ x = \frac{16}{15} + \frac{4}{15} $$,

$$ x = \frac{16 + 4}{15} $$,

$$ x = \frac{20}{15} $$,

$$ x = \frac{4}{3} = 1 \frac{1}{3}. $$

в) $$ \frac{13}{17} - x = \frac{4}{17} $$,

$$ x = \frac{13}{17} - \frac{4}{17} $$,

$$ x = \frac{13 - 4}{17} $$,

$$ x = \frac{9}{17}. $$

Ответ:

a) $$\frac{1}{6};$$

б) $$1 \frac{1}{3};$$

в) $$\frac{9}{17}.$$