The function in this problem should be: f(x) =x² + 12x + 6
y = x² + 12x + 6
y - 6 = x² + 12x
x² ⇒ x x
12x ⇒ 26*x
missing number is 6² = 36
y - 6 + 36 = x² + 12x + 36
(x+6)(x+6) ⇒ x(x+6)+6(x+6) ⇒ x² + 6x + 6x + 36 = x² + 12x + 36
y + 30 = x² + 12x + 36
y = (x+6)² - 30
Choice is D. 36,-36
