ICSE Class 10CISCE
Share
Notifications

View all notifications

The Age of the Father is Twice the Square of the Age of His Son. Eight Years Hence, the Age of the Father Will Be 4 Years More than Three Times the Age of the Son. Find Their Present Ages. - ICSE Class 10 - Mathematics

Login
Create free account


      Forgot password?

Question

The age of the father is twice the square of the age of his son. Eight years hence, the age of the father will be 4 years more than three times the age of the son. Find their present ages.

Solution

Let the present age of the son be x years.
Present age of father = 2x2 years
Eight years hence,
Son’s age = (x + 8) years
Father’s age = (2x2 + 8) years
It is given that eight years hence, the age of the father will be 4 years more than three times the age of the son.
2x2 + 8 = 3(x + 8) +4
2x2 + 8 = 3x + 24 +4
2x2 – 3x – 20 = 0
2x2 – 8x + 5x – 20 = 0
2x(x – 4) + 5(x – 4) = 0
(x – 4) (2x + 5) = 0
x = 4, -5/2
But, the age cannot be negative, so, x = 4.
Present age of son = 4 years
Present age of father = 2(4)2 years = 32 years

  Is there an error in this question or solution?
Solution The Age of the Father is Twice the Square of the Age of His Son. Eight Years Hence, the Age of the Father Will Be 4 Years More than Three Times the Age of the Son. Find Their Present Ages. Concept: Quadratic Equations.
S
View in app×