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Okay sy mass Shmoop for what is the axis of

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symmetry of the parabola given by the equation Negative three

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x squared plus forty two x minus y equals zero

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Okay well first things first let's Add why to both

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sides to write the given equation in standard form right

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y equals mx plus b So here it is y

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equals negative three x squared plus forty two x What

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when a quadratic equation is written in the form why

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equals a x squared plus b x plus c the

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access of symmetry by definition here is the line x

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equals negative b over two a and like you just

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had to know that formula The vertical line passes through

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the vertex in the middle of the problem right there

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So here b is forty two and a is well

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negative three so we've got negative forty two overnegative six

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there and that equals seven So thie axis of awesome

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for the given parable of there is x equal seven

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and that's it The answer is c

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