James and billy have ages that are two consecutive odd integers whose products is 399. Use a quadratic equation to find out the age of each boy if james is the younger of the two boys?

I dont understand how to make the equation and please provide the answers

1 Answer
Aug 4, 2018

Ages of James and billy are 19 and 21 years respectively.

Explanation:

Let the two consecutive odd integers be (2 n-1) and (2 n+1)

Their product is (2 n-1)(2 n+1)=399 or

(2 n)^2- 1^2= 399 or 4 n^2= 399+1 or 4 n^2=400

:. n^2= 400/4 or n^2= 100 :. n = +- 10 :. n = 10

Since age cannot be negative n!=-10.

When n=10 , 2 n-1= 19 and 2 n +1= 21 Therefore,

ages of James and billy are 19 and 21 years respectively. [Ans]