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Okay math people Here we go Another graph Right What

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could be the equation of the line perpendicular to the

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line shown All right so let's stare at that perfect

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ninety degree angle to the line right there Yeah we're

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putting down the sharpie The computer based ccs fire won't

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give you points for defacing school property Perpendicular lines have

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slope with the opposite signs i'ii won will be negative

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The other positive and the values of their slopes will

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be reciprocal Sze Well well positive slopes rise up on

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the y axis as x values increase like goes up

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like that and there's a negative slope of those go

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downwards as x values go up we can make our

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mathematical lives a little easier by eliminating a few of

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these choices right off the bat Since we're looking for

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a line that's perpendicular to the one in the graph

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it happens to have a positive slope so we can

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narrow down the answers to the two with negative slopes

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Right it's got to be either a or b All

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we need to do now is find the slope of

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our graph and take its negative reciprocal Well if we

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started the y you nurse after zero two right there

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and head to the point one five when we move

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up three units and go to the right One unit

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right there Well slope is the ratio of vertical change

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Toe horizontal change so well that's rise of iran and

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the three over one perpendicular lines then have slopes that

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air negative reciprocal sze of each other So a line

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with a slope perpendicular to this one must have a

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slope of negative one third Don't forget the negative in

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there Yeah so it's going to be on the y

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equals mx plus b format It'll be why equals negative

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one third act's minus four so that's it The answer 00:01:40.244 --> [endTime] is b

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