Question 534499
The age of the father is 3 years more than 3 times the age of his son.
 After three years the age of the father will be 10 years more than twice the age of the son.
 Find their present ages? 
:
let f = the father's age
let s = the son's age
:
write an equation for each statement;
:
"The age of the father is 3 years more than 3 times the age of his son."
f = 3s + 3
:
"After three years the age of the father will be 10 years more than twice the age of the son."
f + 3 = 2(s+3) + 10
f + 3 = 2s + 6 + 10
f = 2s + 16 - 3
f = 2s + 13
:
from the 1st statement, replace f with (3s+3)
3s + 3 = 2s + 13
3s - 2s = 13 - 3
s = 10 yrs is the son's age
find Dad's age
f = 3(10) + 3
f = 33 yrs is Dad's age
:
:
Check this in the statement:
"After there years the age of the father will be 10 years more than twice the age of the son. "
33 + 3 = 2(10+3) = 10
36 = 26 + 10