for this problem you simply substitute the values for x and y
2(5/8) + 2/7 =
To simplify this you need to convert 2 to a fraction 2/1 and mutliply that by 5/8 giving you 10/8 + 2/7.
Next find a common denominator. 56 works
70/56 + 16/56 = 86/56 which can be reduced to
43/28