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Today, we are given two points.
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The two points are negative 5, 10, and 7 negative 10.
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And we are supposed to find the equation that essentially lies on these two points.
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We can draw a picture to essentially illustrate the location of these two points.
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So our first point, negative 510, lies in the second quadrant here.
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Again, this is just general.
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This is not exact.
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And our second point 7 negative 10 lies in the fourth quadrant.
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In order to find the equation of these two points, first we need to find the slope.
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Now, our slope is equal to the change in y over the change in x.
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Or in other words, more specifically, y2 minus y1 over x2 minus x1.
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A lot of students always ask, how do i know which y, which point is our first point and which one is our second point? well, our leftmost point, which in this case is going to be negative 510, is going to be our y1 and our x1, and the rightmost point is going to be our y2 and our x2.
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So the left most point is always going to be the first set of points, and the right most point is going to be the second set of points.
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Now we can label these, y2, x2.
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Y1, x1.
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Now that we haven't labeled, we can start plugging in our answers.
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So y2 is negative 10.
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Y1 is going to be 10.
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X2, in our case, is 7.
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And x1 is going to be negative 5.
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We all know that a negative and a negative equals a positive.
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Our answer becomes negative 20 over 12.
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We can still simplify by dividing the top and the bottom by 4.
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And our simplified slope is going to be negative 5 over 3.
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Now that we have our slope, we can derive our equation from point slope formula, which is y minus y1, equal slope times x minus x1.
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And again, this is point slope.
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If you guys forget the point slope formula, it's really easy to derive because it actually comes from the slope.
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Formula itself.
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We see the slow formula...