The age of a father is 2 less than 7 times the age of his son. In 3 years, the sum of their ages will be 52. If the son age is s years, which equation models this situation?
a. (s+3)+[(7s-2)+3}=52
b. 3s+3+3(7s-2)= 52
c. s+(7s-2)=52
d. (s-3)+(7s-2)-3=52