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’s present age is s years, which equation models this situation?

(s+3)+[(7s−2)+3]=52

3s+3+3(7s−2)=52

s+(7s−2)=52

(s−3)+(7s−2)−3=52

Question

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’s present age is s years, which equation models this situation?


(s+3)+[(7s−2)+3]=52



3s+3+3(7s−2)=52



s+(7s−2)=52



(s−3)+(7s−2)−3=52

stamp · Answer

The age of a father f is 2 less than 7 times the age of his son s.

f = 7s - 2

(f + 3) + (s + 3) = 52

stamp · Answer

Substitute into the second equation the equation we derived from the first sentence

stamp · Answer

(7s - 2) + 3 + s + 3 = 52

stamp · Answer

8s + 4 = 52

stamp · Answer

8s = 48

s = 6

stamp · Answer

f = 7s - 2, if s = 6 then

f = 7(6) - 2

f = 42 - 2

f = 40

stamp · Answer

In three years, the son s will be 9 and the father f will be 43.

s + f = 52

9 + 43 = 52

It checks out