Question

The difference of the square number of a number and 9 is equal to 8 times the number. Find the solution.

Answer 1

9, - 1

Explanation:

Let the number be a

a² - 9 = 8a

a² - 8a - 9 = 0

(a - 9) (a + 1) = 0

a - 9 =0, a = 9

a + 1 =0, a = - 1