Решите уравнение: a) 5,23 + x = -7,24; б) y - 2 5/12 = -3 7/15.

Решение: a) $$5,23 + x = -7,24$$ $$x = -7,24 - 5,23$$ $$x = -12,47$$ б) $$y - 2\frac{5}{12} = -3\frac{7}{15}$$ $$y = -3\frac{7}{15} + 2\frac{5}{12}$$ $$y = -\frac{3 \cdot 15 + 7}{15} + \frac{2 \cdot 12 + 5}{12}$$ $$y = -\frac{52}{15} + \frac{29}{12}$$ $$y = -\frac{52 \cdot 4}{15 \cdot 4} + \frac{29 \cdot 5}{12 \cdot 5}$$ $$y = -\frac{208}{60} + \frac{145}{60}$$ $$y = -\frac{63}{60} = -\frac{21}{20} = -1\frac{1}{20} = -1,05$$ Ответ: a) $$x = -12,47$$ б) $$y = -1,05$$