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Okay sy match members We got more quadratic ce for

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you Here we go Except for one All of the

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following paralysis had the same axis of symmetry Which one

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is it If the problem's equation is why equals a

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x squared plus b x plus c like that's the

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standard format for problem than the access of symmetry of

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a parabola is the vertical line x equals negative b

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over two a well assuming this isn't a trick question

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in the same math test is no time for paranoia

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Three of the four parable is shown here need to

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have the same access of symmetry so let's calculate the

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acts of symmetry for the first two choices we've got

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why equals negative three x squared plus for x minus

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five that's a nougat y equal six x squared plus

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eight x plus seven seven b and well let's just

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see what happens if we get the same result We've

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found the access of symmetry common tio three of the

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answer choices So check the other answer choices until we

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stumble on a different answer Yeah we stumble a lot

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around here If we get different results then one of

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the first to answer choices is the exception to the

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norm And that means one of them's The answer Okay

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let's do this thing by the first answer choice has

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an x Squared coefficient equal to negative three and an

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ex coefficient equal toe four So a here is negative

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free and b is for In that case we've got

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negative b over two A there So that gets us

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negative for over two time thing Free or negative for

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negative six or just two thirds Right Well the second

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answer choices a is six there and b is eight

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right there So it's access of symmetry is the formula

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and they're going to be over two way So it's

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negative eight over twelve equals negative two thirds And what

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does that mean Well since we ended up with a

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different result compared to the first choice one of these

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is the exception So it's compared to the third answer

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choice Well a equals fifteen there and b is negative

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Twenty and then we've got a little formula here We

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can plug ins We get negative twenty over too Two

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times fifteen that's thirty and that's Negative of the negative

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twenty over thirty or just positive Two thirds Alright this

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result matches the first answer choice So the second answer

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choice is our exception The answer is b this guy 00:02:13.97 --> [endTime] right here And that's the answer or not

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