WEBVTT
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Okay. We want to find the equation of the
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line that goes through these two points. Actually,
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we just want the segment. Okay, so we
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need the slope and we need the y intercept.
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So to find the slope, we're going to use
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the slope formula. Why? To minus y one
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, which would be negative. 10 minus 10 over
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x two minus x 17 minus negative five. And
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that gives us negative. 20/12. We can reduce
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that to negative 5/3. So the slope of the
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line is negative. 5/3. Now we can find
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the y intercept, and we can use point slope
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form to help us. So point slope form is
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why minus y one equals m times X minus X
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one. We can substitute either one of our points
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in for X one y one. So I'm going
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to use the 1st 1 So I have y minus
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10 equals negative 5/3 times a quantity X minus,
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negative five. And let's simplify that. First of
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all, X minus negative five is the same as
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X plus five. Now we can distribute the negative
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5/3. So if y minus 10 equals negative 5/3
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X, minus 25 3rd and then we'll attend to
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both sides and adding 10 is the same as adding
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33rd. So when we had 33rd to negative 25
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3rd we get 5/3. So this is the equation
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of the line that goes through those two points and
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because we just want the segment, we can restrict
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the domain and we can just have it started negative
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five and end at seven.