In this activity, students identify the coordinates of points necessary to recreate an image. They write a list of ordered pairs that when connected by line segments in order, would recreate a given image.
In the digital version of the activity, students use an applet or graphing technology to recreate an image. The applet allows students to plot points by entering ordered pairs and then connect them using line segments.
If possible, provide access to graphing technology. Demonstrate how to use the technology available in the classroom to plot coordinate pairs. If using the applet or using Desmos in a web browser, consider using these instructions:
Give students 10–12 minutes of quiet work time, and follow with a whole-class discussion.
Use graphing technology to recreate this image. If graphing technology is not available, list the ordered pairs that make up this image. Then compare your list with a partner.
If you have time, consider adding more details to your image such as whiskers, the inside of the ears, a bow, or a body.
For the outline of the head:
| x | y |
|---|---|
| 0 | 2 |
| 2 | 2 |
| 5 | 4 |
| 4.5 | 1 |
| 5 | 0 |
| 5 | -3 |
| 3 | -5 |
| -1 | -5 |
| -3 | -3 |
| -3 | 0 |
| -2.5 | 1 |
| -3 | 4 |
| 0 | 2 |
For the left eye:
| x | y |
|---|---|
| -1 | -0.5 |
| -0.5 | 0 |
| 0 | -0.5 |
| -0.5 | -1 |
| -1 | -0.5 |
For the right eye:
| x | y |
|---|---|
| 2 | -0.5 |
| 2.5 | 0 |
| 3 | -0.5 |
| 2.5 | -1 |
| 2 | -0.5 |
For the nose and mouth:
| x | y |
|---|---|
| -1 | -2.5 |
| 0 | -3.5 |
| 1 | -3 |
| 1 | -2.5 |
| 0.5 | -2 |
| 1.5 | -2 |
| 1 | -2.5 |
| 1 | -3 |
| 2 | -3.5 |
| 3 | -2.5 |
The purpose of this discussion is for students to share the challenges they experienced while graphing the image or determining the coordinates of points and how they overcame them. If not brought up by students, highlight the fact that the image’s line of symmetry was not on the axis, and ask them to share how this affected the coordinates.
If you are using graphing technology, add these statements to the list of things being graphed:
x>6
y>5
x<−4
y<−6
Describe the result. Why do you think that happened?
Sample response: There is a frame around the cat’s face and everything outside it is shaded. This happened because these are the places where it is true that x>6 or y>5 or x<−4 or y<−6.