Question

When the sum of 8 and twice a positive number is subtracted from the square of the? number, 0 results. Find the number.

Answer 1

4

Explanation:

The equation is

x^2 - (2x + 8) = 0 where x is the number to be found.

removing the parentheses by distributing the negative:-

x^2 - 2x - 8 = 0

(x - 4)(x +2) = 0

x = 4, -2.

The value of x must be 4 because it is positive.