Hello,
Let's to remember,
To the perfect square:
X^2 +12x = -6
We would have to add 6^2
Because,
X^2 + 2.(6X) = -6
As (x+k) = x^2 +2xk +k
And,
2xk = 2.6x
xk = 6x
K = 6
Then,
(X+k)^2 = x^2 + 2xk+k^2
= x^2+2.x.6+6^2
= x^2+6x+36
We would to add 36, and would stay:
X^2 + 6X = -6
x^2 +6x + 36 = -6 +36
X^2 +2.6x +6^2 = 30
(X+6)^2 = 30
Answer is the letter A)
