Question

Complete the square x2 – 6x + 8.

Question 3 options:

(x+3)2 – 1


(x-3)2 – 1


(x-3)2


(x-6)2 - 28

Answer 1

(x - 3)^2 - 1.

Explanation:

x2 – 6x + 8.

We divide the coefficient of x by 2:

-6 / 2 = -3 so the contents of the parentheses is x - 3:

x^2 - 6x + 8

= (x - 3)^2 - (-3)^2 + 8

= (x - 3)^2 - 1.

Answer 2

`x^2-6x + 8=x^2-6x+9-1=(x-3)^2-1`