Translating Pictures
Task
Create an interactive activity that allows you to translate a picture by a given vector and explore the characteristics of a translation.
Instructions
1. | Make sure that you have the picture of Bart Simpson saved on your computer before you start the actual construction. | |
2. | ![]() | Create a point A at the coordinates A = (1, 1) using the Point tool. |
3. | ![]() | Select the Image tool and click on point A in order to insert the picture of Bart at this position. |
Hint: GeoGebra will automatically create the second corner point B of the picture. | ||
4. | ![]() | Create point D = (1, 3.9) .
Hint: you might want to enter the coordinates directly into the Algebra Input. |
5. | ![]() | Set point D as the FOURTH corner point of the picture (Properties dialog, tab Position). |
6. | ![]() | Create a rigid triangle ABD using tool Rigid Polygon. Hint: The resulting polygon will keep its shape when moved. It can be moved or rotated by dragging two vertices. |
Try it yourself...
Instructions (continued)
7. | ![]() | Create points O = (0, 0) and P = (3, -2) . |
8. | ![]() | Create vector u = Vector[O, P] .
Hint: You may either use tool Vector or enter the command directly in the Algebra Input. |
9. | ![]() | Translate the picture by vector u using tool Translate by Vector. Hint: You might want to reduce the opacity of the image (Properties dialog, tab Color). |
10. | ![]() | Translate the triangle ABD by vector u. Hint: This will also translate the three corner points A, B, and D by vector u. |
11. | ![]() | Hide point O so it can’t be moved accidentally by using the Show / Hide Object tool. |
12. | ![]() | Change the color and size of objects to enhance your construction using the Style Bar. |
Back to school...
Move the translation vector by dragging point P.