19) $$\frac{8}{15}$$(3$$\frac{3}{4}$$x -$$\frac{5}{16}$$y) -$$\frac{3}{20}$$(6$$\frac{2}{3}$$x -4$$\frac{4}{9}$$y) =

19) $$\frac{8}{15}$$(3$$\frac{3}{4}$$x -$$\frac{5}{16}$$y) -$$\frac{3}{20}$$(6$$\frac{2}{3}$$x -4$$\frac{4}{9}$$y) = $$\frac{8}{15}(\frac{15}{4}x - \frac{5}{16}y) - \frac{3}{20}(\frac{20}{3}x - \frac{40}{9}y) = 2x - \frac{1}{6}y - x + \frac{2}{3}y = x + \frac{3}{6}y = x + \frac{1}{2}y$$

Ответ: $$x + \frac{1}{2}y$$