Решите уравнение
а) (20-2х) ×7=28
б) (9х-15) ÷6=5
в) 72÷(6х+3) =8

Пошаговое объяснение:

a) (20-2х) ×7=28

20 - 2x = 28:7

20 - 2x = 4

2x = 20 - 4

2x = 16

x = 16 : 2

x = 8

б) (9х-15) ÷6=5

9x - 15 = 5 * 6

9x - 15 = 30

9x = 30+15

9x = 45

x = 45:9

x = 5

в) 72÷(6х+3) =8

6x + 3 = 72 : 8

6x + 3 = 9

6x = 9 - 3

6x = 6

x = 1