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Step 1: Group the first 2 terms together, separating them from the constant term.
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Step 2: Factor out leading coefficient, for completing the square to work, the coefficient of x2 must be 1.
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Step 3: Complete the square, Take half of x coefficient and square it. Notice to keep equation balanced you must add this number and subtract it making the net effect zero.
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Step 4: Distribute and add constants.
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Now it is successfully in vertex form and can be easily graphed.
The vertex is at (-3,-2)
The parabola opens up and has a y-intercept at (0, 16)
Here is a graph of this parabola:
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