The sum of mr. brown's age& his sin's age is 38 yrs old this yr.4 yrs ago,mr. Brown was 5 times as old as his son. A. How old is his son this year? B. How old is mr. Brown this year?
B = 38-S
(B-4) = 5(S-4)
Substitute 38-S for B in the second equation and solve for S. Insert that value into the first equation to solve for B. Check by putting both values into the second equation.