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Thank you We sneak and here's your shmoop du jour

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Brought to you by elementary education it's where mr mrs

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watson took their son john on his first day at

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kindergarten That kid with no sherlock Okay check out this

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bar graph The graph above shows total us expenditures for

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elementary and secondary education from nineteen ninety two thousand five

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if a nineteen ninety x equals zero Which of the

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following best models total spending on education and billions of

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dollars at time acts with acts measured in years and

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here's potential answers All right modeling school Well maybe if

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the u s had shelled out a tad more bucks

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we could have had some myth You're looking bar graphs

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like with three d lars special in fact made pyrotechnic

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There you go that's more like it Alright while skimming

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our answer choices It should be pretty clear that we're

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looking to take the information we're given and find a

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way to express it in slope intercept form every answer

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choices in the form why equals mx plus b so

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well let's just start there We're told that in nineteen

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ninety x equals zero and the bar graph shows that

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in that same year federal spending was two hundred forty

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eight point nine billion which will be our why intercept

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groovy on ly We still need slope Where Oh where

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has our slow god Right If we were a slow

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where would we be Well what we need to do

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is take two points and use them to find the

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average rate of change We should take the last point

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In the case of our graph last bar and call

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that fourteen five thirty six by fourteen wealth The first

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bar zero which we've already established Well then this would

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be one to revive a lot Lot fourteen makes sense

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Then we take the first bar which translates point zero

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to forty eight point nine to track the y coordinates

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from one another subject tex coordinates from one another and

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then divide the difference And why coordinates by the difference

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in x co ordinates like so so five Thirty six

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minus two Forty eight point nine to eighty seven point

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one while fourteen minus zero is sixteen Four seven oh

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it no it's fourteen two eighty seven divided by fourteen

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Twenty point five and that's our slow So now we

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can plug in everything we know to get y equals

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Twenty point Five Acts plus 248 point nine And well

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that looks an awful lot like option d If you

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came up with any other answer well we'd have to

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suspect that Something's afoot Very good watson That boy's got 00:02:27.388 --> [endTime] a long way to go

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