10/15 + (5/15 - x) =14/15
10/15 + (1/3 - x) = 14/15
10/15 + 1/3 - x = 14/15
1 - x = 14/15
-x = - 1/15
x = 1/15
/ - дробь
10/15 + (5/15 - x) =14/15
10/15 + (1/3 - x) = 14/15
10/15 + 1/3 - x = 14/15
1 - x = 14/15
-x = - 1/15
x = 1/15
/ - дробь