What number must you add to complete the square x^2+12x=-5

A 12

B 36

C 144

D 6

The general form of a quadratic equation is,

Ax² + Bx + C = 0

A, B, and C are all numerical coefficients of the terms in the equation.

In order to complete the square, we divide all numerical coefficients by 2 and A. Then, square the value of B/2A. Performing this operation for this item,

n = (B/2A) ²

Substituting the known values,

n = (12/2 (1)) ² = 36

Thus, the missing number in this item is 36 and the final expression becomes,

x² + 12x + 36 = - 5 + 36