Let's say Jim's age is x Anna's will be x +4 cuz she is 4 years older than his age the sum of their ages is 25 to make an equation (x+4) + x = 25 combine like terms 2x + 4 = 25 subtract 4 from both sides 2x = 21 now isolate the variable x (Jim's age) x = 10.5 Jim is 10.5
