Question 1051456
x Dan's age, (x+8) Cary's age
In 9 years...
(x+9) + [(x+8)+ 9 ] = 80
2x + 26 = 80
2x = 54
x = 27, Dan's age.  Cary 35
Checking
In 9 years...

 36 + 44 = 80 CHECKS!