Пошаговое объяснение:

[tex]1)8 + 34 \times x = 314 \\ 34x = 314 - 8 \\ 34x = 306 \\ x = 306 \div 34 \\ x = 9[/tex]

[tex]2)20 - 10 \div x = 18 \\ 20 - \frac{10}{x} = 18 \\ - \frac{10}{x} = 18 - 20 \\ - \frac{10}{x} = - 2 \\ 10x = 2 \\ 2x = 10 \\ x = 10 \div 2 \\ x = 5[/tex]

[tex]3)36 - 23 \div x = 13 \\ 36 - \frac{23}{x} = 13 \\ - \frac{23}{x} = 13 - 36 \\ - \frac{23}{x} = - 23 \\ 23 = 23x \\ 1 = x \\ x = 1[/tex]