vertex form is
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basically, just complete the square on the right side
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group x terms together
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factor out linear coefient (number in front of the higest power x, in this case x^2)
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take 1/2 of the linear coefient and square it (4 is linear coefient so take 1/2 of it and square it (4/2=4, 4^2=4)), add positive and negative of it inside the parenthaees (so it equals 0)
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factor perfect square trinomial
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distribute (don't distribute or expand the squared term)
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