Let's call the number we're trying to find "x." According to the problem, we have the equation:

x^2 + 12x = -27

Now, let's solve for x. First, move all terms to one side of the equation:

x^2 + 12x + 27 = 0

Now, this is a quadratic equation. We can try to factor it or use the quadratic formula. In this case, factoring might not be straightforward, so we'll use the quadratic formula:

x = (-b ± √(b² - 4ac)) / (2a)

In our equation, a = 1, b = 12, and c = 27. Plugging these values into the formula:

x = (-12 ± √(12² - 4 * 1 * 27)) / (2 * 1)

x = (-12 ± √(144 - 108)) / 2

x = (-12 ± √36) / 2

Now, simplify further:

x = (-12 ± 6) / 2

Now, we have two possible solutions:

x = (-12 + 6) / 2 = -6 / 2 = -3
x = (-12 - 6) / 2 = -18 / 2 = -9
So, there are two possible values for x: -3 and -9. Since the problem asks for the smaller possible value, the answer is -9.