Question 985023
.
F=age of father; S=age of son
F=4S+5
.
F+S=45
(4S+5)+S=45
5S=40 
S=8 The son is 8 years old.
F=4S+5=4(8)+5=32+5=37 The father is 37 years old.
F-S=37-8=29 ANSWER: The difference in their ages is 29 years.