About this video
The video plots the four corners of a rectangle at (1, 1), (1, 6), (9, 6) and (9, 1). It then finds the rectangle's height as the distance between two corners with the same x-coordinate: from y = 1 to y = 6 is 5 units.
You'll be able to
- plot points in the first quadrant using x for right and y for up.
- find the height of a rectangle from the y-coordinates of its corners.
- check a distance by counting units on the grid.
Key words
- x-coordinate
- The first number; how far to move right of the origin.
- y-coordinate
- The second number; how far to move up from the origin.
- height
- How tall the rectangle is: the vertical distance between its top and bottom.
Transcript
- [Instructor] So we're told here the four corners of a rectangle are located at the points one comma one, one comma six, nine comma six, and nine comma one. Plot the four corners of the rectangle on the coordinate plane below. And they gave us these four points and we can move 'em around with our mouse or our finger depending on what type of a computer we are using.
And so let's just go point by point and plot the green points at those points. So the first one is one comma one. And remember the first coordinate is our X coordinate. The second coordinate is our Y coordinate. So the first coordinate tells us how far do we move to the right of the origin.
So it's one, and then the second coordinate, the Y coordinate, tells us how far to move up from the origin. So that's also a one. So one comma one. The next point is one comma six. X coordinate is one. So we move one to the right of the origin, and then the Y coordinate is six.
So we move six up and notice it's at the intersection of the line, or it's at the intersection of when Y equals six and X equals one. This is one comma six, all right. Now we have nine comma six. So let's see if we take our, if we have X equals nine right over there and Y is equal to six.
So we'd go up six. So notice Y is now equal to six. And we have one last point to plot, nine comma one. So when X is nine, Y is one. We go nine to the right, or we're right above X equals nine. And then we go up one. This is nine comma one. And there you have it.
We have the four corners of our rectangle. Then they say what is the height of the rectangle? Well, if you imagine a rectangle right over here, the height would be the distance between that point and this point, or the distance between that point and that point.
And so what is the distance between these points? Let's see. They both have the same X coordinate and this one is at Y equals six. This is at Y equals one. So this is five higher than this one. So the height is five. And we could also count it. You could see one, two, three, four, five.
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