Номер 909
2/7х + 3/14х – 1/21х = 12/42х + 9/42х – 2/42х = 19/42х
Якщо х = 14/19, то 19/42х = 19/42 • 14/19 = 14/42 = 2/6 = 1/3
Якщо х = 1 2/19, то 19/42х = 19/42 • 1 2/19 = 19/42 • 21/19 = 21/42 = 3/6 = 1/2
2/7х + 3/14х – 1/21х = 12/42х + 9/42х – 2/42х = 19/42х
Якщо х = 14/19, то 19/42х = 19/42 • 14/19 = 14/42 = 2/6 = 1/3
Якщо х = 1 2/19, то 19/42х = 19/42 • 1 2/19 = 19/42 • 21/19 = 21/42 = 3/6 = 1/2