1)
[tex] \frac{6x - y}{4y} = 2 \\ 2 \times 4y = 6x - y \\ 8y = 6x - y \\ - 6x = - y - 8y \\ - 6x = - 9y \\ \frac{x}{y} = \frac{9}{6} \\ \frac{x}{y} = \frac{3}{2} [/tex]
2)
[tex] \frac{y}{x} = 2 \\ y = 2x \\ \frac{x + 3 \times 2x}{2x + 3x} = \frac{7x}{5x} = \frac{7}{5} [/tex]
3)
[tex] \frac{5x - 14y}{7y} = 3 \\ 3 \times 7y = 5x - 14y \\ 21y = 5x - 14y \\ 21y + 14y = 5x \\ 35y = 5x \\ \frac{x}{y} = \frac{35}{5} = 7[/tex]
aici am schimbat a cu x si b cu y, deoarece imi e mult mai usor..
4)
[tex]x + y = 55 \\ \frac {x}{y} = \frac{2}{3} \\ 3x = 2y \\ x = \frac{2y}{3} \\ \frac{2y}{3} + y = 55 \\ 2y + 3y = 165 \\ 5y = 165 \\ y = 33 \\ x = \frac{2 \times 33}{3} = 2 \times 11 = 22[/tex]
