About this video
This video plots the ordered pair (6, -8) on the coordinate plane. It explains that the first number is the x-coordinate (move right or left from the origin) and the second is the y-coordinate (move up or down), so the point is 6 right and 8 down.
You'll be able to
- tell which number in an ordered pair is the x-coordinate and which is the y-coordinate.
- plot a point with a negative coordinate by starting at the origin.
- find a point as the place where an x line and a y line cross.
Key words
- ordered pair
- Two numbers in a set order, (x, y), that give the location of a point.
- origin
- The point (0, 0) where the x-axis and y-axis cross.
- x-axis
- The horizontal number line on the coordinate plane.
- y-axis
- The vertical number line on the coordinate plane.
Transcript
Plot the ordered pair 6, comma negative 8 into the coordinate plane. So this is a coordinate plane right over here. The horizontal axis here, this is the x-axis. The vertical axis here is the y-axis. And the convention, when we get an ordered pair like this, is that the first coordinate is the x-coordinate, and the second coordinate is the y-coordinate.
So they're telling us that we have an x-coordinate of 6. That means we count up 6 on the x-axis. So let's count up 1. I could even write it down-- 1, and then we have 2. That's right there. Then we have 3. Then we have 4. Then we have 5. And then we've moved up 6 along the x-axis.
We started at the origin, at 0, 0. That's the origin. And we moved 6 to the right. That's this part right over here. Now, our y-coordinate is negative 8. That means we move down 8 in the vertical direction. So we can see it right over here. So this right here, I'll just do that every two.
So this is down 1. This right here is negative 2, negative 3. This right here is negative 4, negative 5, negative 6, negative 7, negative 8. So we move to the right 6, and then we move down 8. We move to the right 6, and then we move down 1, 2, 3, 4, 5, 6, 7, and 8.
And we are right over there. So that is the point , 6 negative 8. You could also look at it this way. The x-coordinate is 6. So you move 6 there. And so we're going to be along this line right over here. And then you can go, and then the y-coordinate is negative 8.
So you go down to negative 8. And you say, we're going to be along this line over here. And the place that they intersect is this coordinate. The easiest way I'd like to think of it, move 6 to the right, move along the x-axis, and then move along in the vertical direction along the y-axis.
So you go down 8.
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