ShmoopTube

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For a good time, solve this shmoopy question...

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What is the equation of a line perpendicular to Y equals

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negative 1/2 X plus four and containing the point 8, 2?

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And here are your options...

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Okay, so this question is testing whether we know that in

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the land of Y equals MX plus B

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were M is the slope of a line. The slope of a line

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perpendicular to that line is the negative

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inverse of that form. In this example the slope is negative 1/2

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so we just need that negative reciprocal so that'll be positive

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2 over one or just positive 2. So we can get rid of B and C as potential answers.

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We also know that one point this perpendicular line contains is

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8 , 2. So all we need to do is plug in these points

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into Y equals MX plus B so

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we get 2 equals 2 times

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8 plus B and we have 2 equals 16 plus B

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or B equals -14 and we have Y equals 2x -14

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there you go. The answer is E.

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