5,75 - ( x + 4/7 ) = 2/7
5,75 - ( х + 4/7 ) = 2/7 5,75 - х - 4/7 = 2/7 - х = 2/7 + 4/7 - 5,75 - х = 6/7 - 5,75 - х = 6/7 - 5 3/4 - х = 24/28 - 5 21/28 - х = - 4 25/28 х = 4 25/28 вроде так