My son is 9 less than 1/2 my age. If I am 34 how old is my son?

[math_celebrity]

1/2 of the parent age is 34/2 = 17.

9 less than that is 17 - 9 = 8.

The son is 8 years old.

You can also write this as 1/2(34) - 9 --> 17 - 9 = 8.