2 1/14 - 1 1/9х = 1 5/21
1 1/9х = 2 1/14 - 1 5/21
1 1/9х = 2 3/42 - 1 10/42 = 1 45/42 - 1 10/42 = 35/42 = 5/6
х = 5/6 : 1 1/9 = 5/6 : 10/9 = 5/6 * 9/10 = 3/4
х = 3/4
2 1/14 - 1 1/9х = 1 5/21
1 1/9х = 2 1/14 - 1 5/21
1 1/9х = 2 3/42 - 1 10/42 = 1 45/42 - 1 10/42 = 35/42 = 5/6
х = 5/6 : 1 1/9 = 5/6 : 10/9 = 5/6 * 9/10 = 3/4
х = 3/4