Answers: Choice A, choice B, choice C
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Step-by-step explanation:
A quadratic equation has 2 as the largest exponent. This rules out something like
(choice F).
For a quadratic to be in standard form, it must fit the template of
. We must have all terms to one side, with zero on the other side, so this rules out choice D.
Choice E is ruled out because we need to expand out the
portion to get that equation into standard form. Choice E is currently in vertex form instead.
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Choices A, B and C are all quadratics in standard form
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For instance, choice A has: