Question

75
Найдите неизвестный член пропорции (75,76):
1)х:20=2:5
2)х:18=7:9
76.1)8/14=х/35
2)7/28=х/12
пж срочнооо пж​

Answer 1

Ответ:

$x \div 20 = 2 \div 5 \\5x = 20 \times 2 \\ 5x = 40 \\ x = 8$

$x \div 18 = 7 \div 9 \\ 9x = 18 \times 7 \\ 9x = 126 \\ x = 14$

$\frac{8}{14} = \frac{x}{35} \\ \\ 14x = 35 \times 8 \\ 14x = 280 \\ x = 20$

$\frac{7}{28} = \frac{x}{12}$

$28x = 7 \times 12 \\ 28x = 84 \\ x = 3$