Problem

Convert the equation to standard form by completing the square on $x$ or $y$. Then find the vertex, focus, and directrix of the parabola. Finally, graph the parabola.
\[
x^{2}+12 x-12 y+12=0
\]

Answer

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Answer

Thus, the vertex is \(\boxed{(-6, -2)}\), the focus is \(\boxed{(-6, 1)}\), and the directrix is \(\boxed{y = -5}\).

Steps

Step 1 :First, we rewrite the equation in the form of a parabola. We can rewrite the equation as \(x^2 + 12x = 12y - 12\).

Step 2 :Then, we complete the square on the left side of the equation. We add \((12/2)^2 = 36\) to both sides of the equation to get \((x + 6)^2 = 12y - 12 + 36\).

Step 3 :Simplify the equation to get \((x + 6)^2 = 12(y + 2)\).

Step 4 :Now, we can see that the equation is in the standard form of a parabola \((x - h)^2 = 4a(y - k)\), where \((h, k)\) is the vertex of the parabola, and \(a\) is the distance from the vertex to the focus and the directrix.

Step 5 :From the equation, we can see that the vertex of the parabola is \((-6, -2)\).

Step 6 :Also, we can see that \(4a = 12\), so \(a = 3\).

Step 7 :Since the parabola opens upwards, the focus of the parabola is \((h, k + a) = (-6, -2 + 3) = (-6, 1)\).

Step 8 :The equation of the directrix is \(y = k - a = -2 - 3 = -5\).

Step 9 :Finally, we can graph the parabola with the vertex at \((-6, -2)\), the focus at \((-6, 1)\), and the directrix at \(y = -5\).

Step 10 :Thus, the vertex is \(\boxed{(-6, -2)}\), the focus is \(\boxed{(-6, 1)}\), and the directrix is \(\boxed{y = -5}\).

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