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Okay shmoop furs Just two more math questions in this

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section Review our little formula sheet here right there All

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right let's Get into it to birds are migrating due

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north First flight five thousand Eventually something passes The secondary

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begins its journey forty five mile directly north of the

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first bird Second replies an average of twenty miles an

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hour flying thing kind of representing flight time hours which

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inequality represent the length of time for the first bird

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gets ahead of second All right great question here All

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right We're going to need a little bit of modeling

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a little bit of chart in here So let's think

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about it The birds flights can be modelled as a

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linear equation on a graph with the speeds being the

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slopes of those lines And we need to account for

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the fact that the second bird is forty five miles

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ahead at the beginning So these air the equations for

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the distances traveled by the two birds right Burn one

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is just thirty five t right it's house fast she's

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going and bird two is twenty plus forty five A

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little bit ahead Remember they're going both due north this

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kind of complex and you've got to really think about

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where these lines are going to intersect All right well

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we cleverly named the bird's bird one and bird to

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hopefully they don't get offended We can only use the

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information we're given notice that bird one is initially behind

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right here But after the grafts intersect in the two

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birds high five in the air ever rooms do with

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their wings Bird one pulls ahead of bird to there's

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a way to represent Their flight paths algebraic li the

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question asked for wind bird one is ahead of bird

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too So set the equation inverted one to be greater

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than that of bird too So we get thirty five

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t is greater than twenty plus forty five Now we

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isolate the t yeah we're going fast here We know

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but the is testing whether you showed up in school

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that day so isolate t we got thirty five t

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minus twenty is greater than forty five and you can

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treat these greater than things like their equal things and

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we've got fifteen tea then right Thirty five hundred twenty

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fifteen so fifteen tea is greater than forty five so

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tea is greater than three So what does that mean

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While the inequality that represents the length of time that

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the first bird is ahead of the second bird is

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t is greater than three so it's just a if

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we worried to distraction over the thought of the two

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birds colliding in midair we may have subtracted thirty five

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miles an hour from the initial forty five mile advantage

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but we can't do that because they're both headed north

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from presumably different directions There or calculated the difference between

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the two speeds which on its own doesn't help us

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And both of these answers would have been incorrect So

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yeah it's a And uh just beware of the birds 00:02:28.148 --> [endTime] hitting each other That would be sad

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