Question

If I multiply a number by 10 and subtract 9,
I get the square of the number.
What could the number be?

Answer 1

n = the number
10n - 9 = n2
0 = n2 - 10n + 9
0 = (n - 1)(n - 9)

{ 1, 9 }

The number could be either 1 or 9.

Answer 2

Answer:

The two numbers which satisfy the given statement are 1 and 9

Step-by-step explanation:

Given as :

A number is multiply by 10 and subtracted 9 , then square of number is formed :

So, Let The number be x

Or, ( 10 × x ) - 9 = x²

Or,  10 x - 9 = x²

Or,   x² - 10 x + 9 = 0

Or,   x² - x - 9 x + 9 = 0

Or,   x ( x - 1 ) - 9 ( x - 1 ) = 0

so,  ( x - 1 ) ( x - 9 ) = 0

∴    x = 1    and  x = 9

Hence The two numbers which satisfy the given statement are 1 and 9 Answer