Задание 2. Найдите корень уравнения.
1) $$x-\frac{x}{18}=-\frac{34}{9}$$
$$\frac{18x-x}{18}=-\frac{34}{9}$$
$$\frac{17x}{18}=-\frac{34}{9}$$
$$17x=-\frac{34 \cdot 18}{9}$$
$$17x = -34 \cdot 2$$
$$17x = -68$$
$$x = \frac{-68}{17}$$
$$x = -4$$
Ответ: x = -4
2) $$-5+\frac{x}{3}=\frac{x+8}{6}$$
$$-\frac{5}{1} + \frac{x}{3} = \frac{x+8}{6}$$
$$-\frac{5 \cdot 6}{1 \cdot 6} + \frac{x \cdot 2}{3 \cdot 2} = \frac{x+8}{6}$$
$$-\frac{30}{6} + \frac{2x}{6} = \frac{x+8}{6}$$
$$-30 + 2x = x + 8$$
$$2x - x = 8 + 30$$
$$x = 38$$
Ответ: x = 38
3) $$\frac{7x+2}{4}+1=\frac{5x}{3}$$
$$\frac{7x+2}{4} + \frac{1}{1} = \frac{5x}{3}$$
$$\frac{3(7x+2) + 1 \cdot 12}{12} = \frac{4 \cdot 5x}{12}$$
$$3(7x+2) + 12 = 20x$$
$$21x + 6 + 12 = 20x$$
$$21x + 18 = 20x$$
$$21x - 20x = -18$$
$$x = -18$$
Ответ: x = -18
4) $$\frac{16}{x+3}=-\frac{8}{11}$$
$$16 \cdot 11 = -8(x+3)$$
$$176 = -8x - 24$$
$$8x = -24 - 176$$
$$8x = -200$$
$$x = \frac{-200}{8}$$
$$x = -25$$
Ответ: x = -25
5) $$\frac{5}{x+9}=-2$$
$$5 = -2(x+9)$$
$$5 = -2x - 18$$
$$2x = -18 - 5$$
$$2x = -23$$
$$x = \frac{-23}{2}$$
$$x = -11.5$$
Ответ: x = -11.5
6) $$\frac{5}{x-12}=\frac{12}{x-5}$$
$$5(x-5) = 12(x-12)$$
$$5x - 25 = 12x - 144$$
$$5x - 12x = -144 + 25$$
$$-7x = -119$$
$$x = \frac{-119}{-7}$$
$$x = 17$$
Ответ: x = 17