3. Решить уравнения: 411 A)y- = 9 12 21 9 Б)-у = 24 48

1. A) $$y - \frac{4}{9} = \frac{11}{12}$$ $$y = \frac{11}{12} + \frac{4}{9}$$ Общий знаменатель 36. $$\frac{11}{12} = \frac{11 \cdot 3}{12 \cdot 3} = \frac{33}{36}$$, $$\frac{4}{9} = \frac{4 \cdot 4}{9 \cdot 4} = \frac{16}{36}$$ $$y = \frac{33}{36} + \frac{16}{36} = \frac{33 + 16}{36} = \frac{49}{36} = 1\frac{13}{36}$$
2. Б) $$\frac{21}{24} - y = \frac{9}{48}$$ $$y = \frac{21}{24} - \frac{9}{48}$$ Общий знаменатель 48. $$\frac{21}{24} = \frac{21 \cdot 2}{24 \cdot 2} = \frac{42}{48}$$ $$y = \frac{42}{48} - \frac{9}{48} = \frac{42 - 9}{48} = \frac{33}{48} = \frac{11}{16}$$

Ответ: A) $$y = 1\frac{13}{36}$$; Б) $$y = \frac{11}{16}$$