Question

(5/7-2/3x)×21=1
Решите уравнение

Answer 1

5/7 - 2/3х = 1/21
15/21 - 2/3х = 1/21
2/3х = 14/21
х = 14/21 : 2/3
14/21 : 2/3 = 14/21 × 3/2 = 42/42 = 1
х = 1.