28 - (x - 6 1/7) = -4 3/4;
28 - x + 6 1/7 = -4 3/4;
x = 28 + 6 1/7 + 4 3/4;
x = 38 + 1/7 + 3/4;
x = 38 + 4/28 + 21/28;
x = 38 + 25/28 = 38 25/28;
28 - (x - 6 1/7) = -4 3/4;
28 - x + 6 1/7 = -4 3/4;
x = 28 + 6 1/7 + 4 3/4;
x = 38 + 1/7 + 3/4;
x = 38 + 4/28 + 21/28;
x = 38 + 25/28 = 38 25/28;