Question

The product of ages of a man 5 years ago and
5 years hence is 600, find his present age.​

Answer 1

25

Explanation:

let his age be x, then

5 years ago his age was x - 5 and in 5 years will be x + 5 , thus

(x - 5)(x + 5) = 600 ← expand factors using FOIL

x² - 25 = 600 ( add 25 to both sides )

x² = 625 ( take the square root of both sides )

x =
`√(625)` = 25

Answer 2

`\boxed{Age \ of \ man = 25 \ years}`

Explanation:

Let the age be x

Then, the given condition is:

(x-5)(x+5) = 600 [ x-5 for age 5 years ago and x+5 for age 5 years after ]

Using Formula
`(a+b)(a-b) = a^2-b^2`

`x^2-25 = 600`

Adding 25 to both sides

`x^2 = 600+25`

`x^2 = 625`

Taking sqrt on both sides

`x = 25` years