We can use the system of equations:x + y = 217x - y = 85-----------------From the 2nd equation: y = x - 85x + x - 85 = 2172 x = 217 + 852 x = 302x = 302 : 2x = 151y = 217 - 151y = 66We can prove this solution:151 + 66 = 2017 and 151 - 66 = 85.Answer: those numbers are 151 and 66.