Question

The square of 9 less than a number is 3 less than the number, What is the number?

Answer 1

78

Explanation:

The square of 9 is 9^2 which implies 9 × 9 = 81

Let the unknown number be represented by X. Thus,

9^2 - x = 3

81 - x = 3

Add x to both sides

81 - x + x = 3 + x

81 = 3 + x

Subtract 3 from both sides

81 - 3 = 3 - 3 + x

78 = x

x = 78

Check

81 - x = 3

Since x = 78

81 - 78 = 3