Question

Решите
У+3/8
----------------=4/7
7/20-7/8

Answer 1

Решить уравнение.

$\dfrac{y + \frac{3}{8}}{\frac{7}{20} - \frac{7}{8}} = \dfrac{4}{7};\\y + \dfrac{3}{8} = \dfrac{4}{7}\left(\dfrac{7}{20} - \dfrac{7}{8}\right);\\y + \dfrac{3}{8} = \dfrac{7}{20}*\dfrac{4}{7} - \dfrac{7}{8}*\dfrac{4}{7};\\y + \dfrac{3}{8} = \dfrac{1}{5} - \dfrac{1}{2};\\y + \dfrac{3}{8} = \dfrac{2 - 5}{10};\\y + \dfrac{3}{8} = -\dfrac{3}{10};\\y = -\dfrac{3}{10} - \dfrac{3}{8};\\y = \dfrac{-12 - 15}{40};\\y = -\dfrac{27}{40}.$

Ответ: $-\dfrac{27}{40}$.