Difference between revisions of "Geogebra/C2/Symmetrical-Transformation-in-Geogebra/English-timed"

|'''Time'''

|'''Narration'''

|Hello everybody. Welcome to this tutorial on '''Symmetrical Transformation''' in '''Geogebra'''.  

| Line symmetry Rotation symmetry  

|and also learn to enlarge figure with scale and position.  

|Reflect Object about Line  

|Rotate Object around Point by Angle  

|Dilate object from a Point by Factor  

|Semicircle through Two points  

| Regular Polygon and  

|Perpendicular bisector  

| Is also called as '''Line symmetry'''.

|A type of symmetry where one half is the reflection of the other half.

|You could fold the image and have both halves match exactly.  

|Line of Symmetry is the line over which the figure is reflected.

|Let's switch to Geogebra window.

|Click on the point D.This will highlight point D.

|What do you notice ? Here perpendicular bisector is the line of symmetry.

|Let's draw a semicircle.Click on the '''Semicircle through Two points''' tool. Mark point E and then F.  

|Right click on the line, '''Object Properties'''. Click on '''Style''', change Style.  

|Click on '''File''' '''Save As'''.

|click on '''File''' '''New'''.

|Click on '''OK'''.

|Select the option '''clockwise'''. Click on '''OK'''.

|Next, let's '''dilate''' or '''enlarge object from point by factor.'''  

|'''Dilation''':

|in which a figure is enlarged using a scale factor.

|Let's draw a triangle using the '''Polygon'''tool,

|E , F , G. Click on E again to complete the triangle.

|Click on '''New Point''' tool and

|mark a point '''H'''.

|Click on '''Dilate Object from Point by Factor''' tool.

|Click on the triangle '''EFG'''.

|This will highlight the triangle.

|Click on the point 'H'.

|A dialog box opens.

|Type value of 2 in the number field.

|Click on '''OK'''.

|This will dilate or enlarge the object twice.

|Click on segment between two Points, join points H,E,E'.

|join points H,G,G'.

|join points H,F,F'.

|Here, you can see that H is the point of dilation.

|You can enlarge object as many number of times as you wish, by typing the value of '''Factor'''.

|Let us save this file now.

|Click on '''File''' >> '''Save As'''.

|I will type the file name as '''Dilate-triangle'''.

|Click on '''Save'''. With this we come to the end of this tutorial.

|Let's summarize.

|In this tutorial we learnt:

|Reflection about a line.

|Rotation of an object at a point.

| Enlargement of an object by a scale factor.

|As an assignment I would like you to:

|Draw a pentagon.Use '''Regular Polygon''' tool to draw. (Hint:sides=5).

|Draw a perpendicular bisector to one of the sides of the pentagon.

|Create a point inside the pentagon.

|Set '''Trace On''' for the point.

|Get reflection of the point about the perpendicular bisector.

|Set '''Trace On''' for the image point.

|Trace the pentagon to see if you have selected the correct line of symmetry.

|Rotate the original pentagon counter clockwise in 135° at a point.

|Dilate the pentagon at a point by the factor of 3.

|The assignment should look like this.

|Watch the video available at this URL.

|It summarizes the Spoken Tutorial project.

|If you do not have good bandwidth,you can download and watch it.

|The Spoken Tutorial Project Team : Conducts workshops using the spoken tutorials.

|Gives certificates to those who pass an online test.

|For more details, please write to contact@spoken-tutorial.org.

|Spoken Tutorial Project is a part of the Talk to a Teacher project.

|It is supported by the National Mission on Education through ICT, MHRD, Government of India.

|This is Neeta Sawant from SNDT University Mumbai, signing off.Thanks for joining.