Question

помогите уравнение решить​

Answer 1

Ответ:

1)

$(7x - 1)(2 + 5x) = 0 \\ {\displaystyle{\begin{cases} 7x - 1 = 0 \\ 2 + 5x = 0 \end{cases}}} \: \: \: = > \\ {\displaystyle{\begin{cases}7x = 1 \\ 5x = - 2 \end{cases}}} \: \: \: = > \\ {\displaystyle{\begin{cases} x = \frac{1}{7} \\ x = - \frac{2}{5} \end{cases}}} \\ x_{1} = - 0.4 \: \: \: \: \: \: \: x _{2} = \frac{1}{7}$

2)

$36 {y}^{2} - 49 = 0 \\ 36 {y}^{2} = 49 \\ {y}^{2} = \frac{49}{36} \\ y = \pm \sqrt{ \frac{49}{36} } \\ y = \pm \frac{7}{6} \\ \\ y = \pm1 \frac{1}{6}$

3)

$\frac{1 + 4x}{3x - 5} = 0$

$3x - 5≠0 \\ 3x≠5 \\ x≠ \frac{5}{3}$

$1 + 4x = 0 \\ 4x = - 1 \\ x = - \frac{1}{4} \\ x = - 0.25$