4. Решим уравнения:
a) $$3\frac{8}{9} - x = 1\frac{5}{9}$$
$$x = 3\frac{8}{9} - 1\frac{5}{9} = 2\frac{3}{9} = 2\frac{1}{3}$$
Ответ:$$x = 2\frac{1}{3}$$
б) $$(y-8\frac{12}{19})+1\frac{7}{19}=6\frac{2}{19}$$
$$y-8\frac{12}{19}=6\frac{2}{19}-1\frac{7}{19}$$
$$y-8\frac{12}{19}=4\frac{14}{19}$$
$$y=4\frac{14}{19}+8\frac{12}{19}=12\frac{26}{19}=13\frac{7}{19}$$
Ответ:$$y=13\frac{7}{19}$$