A father is 9 times as old as his son. In three years, the father will be 6 times as old as his son.
How old is the son?
f = 9s
in three years
f+3 = 6 (s+3) sub in the red equation
9s + 3 = 6s + 18
3s = 15
s = 5 y/o
f = 9s
in three years
f+3 = 6 (s+3) sub in the red equation
9s + 3 = 6s + 18
3s = 15
s = 5 y/o