WEBVTT
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Hello.
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Hi, everybody.
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Hi, everybody.
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Hi, everybody.
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Okay.
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What I'd like to do is show you guys how to find the slope of the line graph to the right.
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Right? Now, there's a couple ways we can do this properly.
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And what we're going to do is first, we need to determine what are our coordinate points.
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And here is our x-axis.
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And here's our y-axis.
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So we have a point right here.
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So we need to determine what, from my point, my origin, 0, 0,
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what do I have to do to get this point?
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Well, I don't have to move left or right.
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So my x-value is 0.
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However, I do have to go up to unit.
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So it's 0, 2.
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Then, over for this point, I have to go to the right, 1, 2, 3, 4, 5, 6, 7.
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So I can say this point is 7.
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That's the x-value.
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And then the y-values, how far down do I have to go from my origin?
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Which is 1, 2, 3, 4, 5, 6.
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So since I'm going down, I'm going to make it a negative 6.
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All right?
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Now, there's two ways we can do this, ladies and gentlemen.
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We can use these coordinate points or we can do what we call a slope triangle.
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To do a slope triangle, what you're going to do is you're going to follow the grid lines
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and make a right triangle.
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Meaning it's going to have a right angle.
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So make the vertical and the horizontal line to find a slope triangle.
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Now, what we can do is we can find what is the length of the line.
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And find what is the length between these two points.
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How far did I change from my leftmost point to my rightmost point?
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And it's very easy visually just to count to count.
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So for me, I go over 1, 2, 3, 4, 5, 6, 7.
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So that was my change in my x-or-y-values.
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Which one goes left or right?
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x-values, guys.
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That's my x-axis.
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So if I'm moving left or right, that's the change in my x-coordinates.
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All right?
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We could also do it like this.
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Take your x-value, which is 7.
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Take your other x-value, which is 0, and subtract them.
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So you could also say 7 minus 0.
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Remember, x-values are on the bottom?
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Then I need to find the y-values.
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So between these two points, how far did I travel?
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Now I traveled down, but I traveled, how many units?
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1, 2, 3, 4, 5, 6, 7, 8 units.
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So therefore I traveled 8 units.
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However, did I travel up or down?
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Travel down, right?
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So therefore, since I traveled down, it's going to be down 8.
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Please don't be here.
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So the other way I could say that is now instead of subtracting my x from each other,
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I could say negative 6 minus 2, which is the same thing as negative 8 over 7.
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Now some of you might have gotten a different answer.
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Some of you might have said, oh, I'm just going, I got 8 over negative 7.
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And how would you get that answer?
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Well, you guys can also have done a slope triangle going up and to the left.
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You guys noticed you also couldn't have done a triangle like this.
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Well, if you do a triangle like this, if you go up, you went up, still 8 units, right?
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You still went up 8 units, but since you went up, that would have been positive.
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So you guys would have had a positive 8, and then, to right to left, you still went over 7 units,
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but it would have gone over 7 units to the left.
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And when you travel to the left, that means you're going in the negative direction.
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So you would have got a negative 7.
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Here comes the question, is negative 8 divided by 7, the same thing as 8 divided by negative 7?
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And yes, they're both going to give you a negative 8.
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So that is my slope for that line.
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Okay?
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That's it.