Step by step explanation: Five years ago, John's age was half of the age he will be in 8 years. this means that (x-5) = (x+8)/2 ----- solving for x, we get: 2 * (x-5) = x + 8 which becomes: 2x - 10 = x + 8 which becomes: x = 18 ----- john is 18 years old now. 5 years ago john was 13 8 years from now john will be 26 13 = 1/2 * 26