ShmoopTube

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Thank you We sneak in lines as models for distance

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rate and time Allah shmoop alright A train leaves from

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one station traveling sixty miles an hour After twenty minutes

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it passes a train leaving from another station forty miles

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away from the first what's the name of the conductor

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Well you probably had your fill of these distance rate

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in time Problems in math class is over the years

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But what in the world did they have to do

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with your life Like who takes the train anymore anyway

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Well good news Even if you've never set foot on

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a train in your life Problems like this can help

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you understand relationships between time speed and distance in the

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best way for them to do that is to express

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them as lines on a graph This all right So

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yeah we're gonna have to plot some point Let's call

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our axes Time and distance right here Now we can

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put a point at ten Ten That is when ten

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minutes of gun by our first train moving at sixty

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miles every sixty minutes has gone ten miles it's a

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mile a minute then at twenty twenty thirty thirty and

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so on we brought away Now for a second train

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We now know that train number one went twenty miles

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in twenty minutes The second station was forty miles away

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from the first and it arrived in the same midpoint

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in the same amount of time Well then it also

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went twenty miles in twenty minutes ten miles ten minutes

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a mile a minute using advanced calculus there the exact

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same line Okay so we may not know that the

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conductor's name is moshe but we just figured out that

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the two trains are traveling at the same speed simply

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by looking at two lines and comparing their slope which

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in this case i happen to be identical L know

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what we should really be concerned about is the slope

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that train number one is now approaching Anyone know where 00:01:43.511 --> [endTime] the brakes are in this thing

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