Question

Find the number which exceeds its positive square root by 20.

Answer 1

Let The Number be x
According to the given Question

√x + 20 = x
√x = x - 20

Squaring both the sides

x = x² + 400 - 40x
[ (a - b)² = a² - 2ab + b² ]

x² - 41x + 400 = 0
x² - 16x - 25x + 400 = 0
x(x - 16) - 25(x - 16) = 0
(x - 16)(x - 25) = 0

ANS = x is equal to 25 or 16 both are correct answers

Hope you understand.
Thank you :)