214k views
4 votes
Eric works as a manager with an international hotel. Eric has a son who is 30 years younger than him. The product of their ages is 175 years. How old is Eric?

1 Answer

2 votes
ANSWER

Eric is

35years

Step-by-step explanation

Let Eric's age be

x \: \: years

Then his son age will be,


(x - 30) \: years

The product of their ages is 175.

This implies that,


x(x - 30) = 175

We expand to get,



x^2- 30x = 175

We equate everything to zero to obtain,


{x}^(2) - 30x - 175 = 0

We split the middle term to get,


{x}^(2) +5x- 35x - 175 = 0

We factor to obtain,


x(x +5)- 35(x +5) = 0

We factor further to get,


(x - 35)( x + 5) = 0

This implies that,


x = 35 \: or \: - 5

Since age is not negative,


x = 35years

Therefore Eric is

35years
User ArkadyB
by
7.9k points