Question

The sum of the present age of the father and his daughter is 42 years. 7 years later, the father will be 3 times old than the daughter. the present age of the father is

Answer 1

let x =father's present age and y =daughter's present age
 - first equation 
7 years later:
x+7 =father's age y+7=daughter's age

 - second equation 
use either elimination or substitution on the two equations

by substitutioN



Father's present age: 35