The sum of the ages of a father and his son is 45 years. Five years ago the product of their ages was 124. Taking the son's present age as x gives x^2 - 45x + 324 = 0. Find the son's present age (years) using the quadratic formula.

Question

Accepted Answer

9. D = 45^2 - 4(324) = 2025 - 1296 = 729, √D = 27. x = 45 ± 27/2 = 36 or 9. The son's age must be less than the father's, so x = 9 (father 36). Check 5 years ago: 4*31 = 124.

The sum of the ages of a father and his son is 45 years.
Five years ago the product of their ages was 124.
Taking the son's present age as $x$ gives $x^{2} - 45 x + 324 = 0$ .
Find the son's present age (years) using the quadratic formula.

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More Class 10 The Quadratic Formula practice

The sum of the ages of a father and his son is 45 years.Five years ago the product of their ages was 124.Taking the son's present age as x gives x2−45x+324=0.Find the son's present age (years) using the quadratic formula.

Step-by-Step Solution

Master this chapter in 30 minutes a day.

More Class 10 The Quadratic Formula practice

The sum of the ages of a father and his son is 45 years.
Five years ago the product of their ages was 124.
Taking the son's present age as $x$ gives $x^{2} - 45 x + 324 = 0$ .
Find the son's present age (years) using the quadratic formula.