Question

The sum of a natural number and its square is 42. Find the number​

Answer 1

Answer: 6

Explanation:

Let the natural number = x

∴ According to the question,

x + x² = 42

⇒ x² + x - 42 = 0

⇒ x² +7x -6x -42 = 0                   (By middle term splitting)

⇒ x (x + 7)- 6 (x +7) = 0

⇒ (x - 6) (x + 7) = 0

⇒ x - 6 = 0   OR   x + 7 = 0

⇒ x = 6  OR  x = -7

But, x is a natural number, thus x cannot be negative.

Hence, x = 6

Proved.

Hope you got that.

Thank You.