Mathematical Olympiad problems must be solved by linear equation of one variable The son said, "my age is nine years younger than half of my father's age." the father said, "my age is three times more than my son's age, three years older." Q: how old are my son and father You have to solve it with equations

Mathematical Olympiad problems must be solved by linear equation of one variable The son said, "my age is nine years younger than half of my father's age." the father said, "my age is three times more than my son's age, three years older." Q: how old are my son and father You have to solve it with equations

Let the age of the son be x years old
So: the son said, "I'm nine years younger than half my father's age."
At this time, father's age is: 2 (x + 9)
The father said, "I'm three times as old as my son, three years old."
At this time, my father's age is 3x + 3
Therefore, 2 (x + 9) = 3x + 3
The solution is: x = 15
Father's age: 3 * 15 + 3 = 48 years old