3.
[tex]a) \ x-\frac{x}{2} = x-\frac{1}{2}x = \frac{1}{2}x\\\\b) \ y-\frac{y}{5} = y-\frac{1}{5}y = \frac{4}{5}y\\\\c) \ \frac{a}{3}+a = \frac{1}{3}a + a = 1\frac{1}{3}a\\\\d) \ \frac{z}{7}-z = \frac{1}{7}z - z = -\frac{6}{7}z\\\\e) \ \frac{x}{2}-\frac{x}{4} = \frac{1}{2}x - \frac{1}{4}x = \frac{2}{4}x - \frac{1}{4}x = \frac{1}{4}x\\\\f) \ \frac{y}{2}+\frac{y}{5} = \frac{1}{2}y + \frac{1}{5}y = \frac{5}{10}y + \frac{2}{10}y = \frac{7}{10}y[/tex]
4.
[tex]a) \ x - 0,1x = 0,9x\\\\b) \ \frac{3}{7}y - y = -\frac{4}{7}y\\\\c) \ 2\frac{3}{5}a - 3a = 2\frac{3}{5}a - 2\frac{5}{5}a = -\frac{2}{5}a\\\\d) \ 0,25w - w = -0,75w\\\\e) \ 3z - 1\frac{3}{7}z = 2\frac{7}{7}z - 1\frac{3}{7}z =1\frac{4}{7}z\\\\f) \ 0,1z - 2,5z = -2,4z[/tex]
[tex]g) \ 2,5y + y - 0,2y = 3,5y - 0,2y = 3,3y\\\\h) \ 3y-1\frac{1}{3}y + y = 4y-1\frac{1}{3}y = 3\frac{3}{3}y -1\frac{1}{3}y = 2\frac{2}{3}y\\\\i) \ \frac{3}{4}x - 1,5x - 2x = 0,75x - 3,5x = -2,75x[/tex]
