Geogebra/C2/Symmetrical-Transformation-in-Geogebra/English

Title of script: Symmetrical Transformation in Geogebra

Author: Neeta Sawant

Keywords: Symmetry-line and Rotation, Reflect Object about Line, Rotate Object around Point by Angle, Dilate object from a Point by Factor, Semicircle through Two points, Dilation, Set trace On, video tutorial

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Visual Cue	Narration
Slide Number 1	Hello everybody. Welcome to this tutorial on Symmetrical Transformation in Geogebra
Slide Number 2 Learning Objectives	In this tutorial we will learn Symmetrical transformations such as Line symmetry Rotation symmetry and also learn to Enlarge figure with scale and position
Slide Number 3 Pre-requisites	We assume that you have the basic working knowledge of Geogebra If not, For relevant tutorials on Geogebra. Please visit our website http://spoken-tutorial.org
Slide Number 4 System Requirement	To record this tutorial I am using Ubuntu Linux OS Version 11.10 Geogebra Version 3.2.47.0
Slide Number 5 GeoGebra Tools used in this tutorial	We will use the following Geogebra tools 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
slide Number 6 Definition of Transformation	Symmetrical transformation of a geometric figure is - A change in its position, size or shape on a coordinate plane Original figure is called 'Object' Transformed figure is called 'Image'
Slide Number 7 Reflection symmetry	Reflection symmetry 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
Switch to GeoGebra window Dash home >>Media Apps>>Under Type >>Education>>Geogebra	Let's Switch to GeoGebra window Dash home >>Media Apps>>Under Type >>Choose Education>> and Geogebra
Click on Close button on Algebric view	For this tutorial I am closing the Algebric view Click on Close button on Algebric view
	Let's start with “Line of symmetry”
Click on “Polygon” tool >> To Construct a triangle	First let's construct an equilateral triangletriangle Select “Regular Polygon” tool from toolbar.
Click on drawing pad Points 'A' ,'B' >>enter 3 click Ok	Click on drawing pad points 'A' ,'B', and enter 3 for the number of sides. An equilateral triangle 'ABC' is drawn
Select “Perpendicular Bisector Tool” >> click on side AC	Let's draw a perpendicular bisector to one of the sides of the triangle Select “Perpendicular Bisector Tool” and click on side AC
Select the Point tool >> create a point D Right click on point D >> select Trace ON Click on Reflect Object about Line	Select the Point tool and create a point D . Move the point D towards one of the vertices . Right click on point D and select Trace ON Select “Reflect Object about Line”tool from the tool bar
Click on the Point D	Click on the Point D This will highlight Point D
Click on perpendicular Bisector	Click on perpendicular Bisector This will produce reflected image D' on the other side of perpendicular bisector
	'D is mirror image of point 'D' Set Trace On for the point D'
	Let us move the point D along the triangle using Move tool
Click on the “Move” tool	Click on the first option under Move tool from the toolbar
Drag the object	Click on figure with the mouse. Drag it tracing the triangle . Now release the mouse button. What do you notice ? Here perpendicular bisector is the line of symmetry D is the object and D' is the image
	Let's reflect a semicircle about a line
Click on the “Semicircle through Two points” tool >>Mark points E and F	Let's draw a semicircle Click on the “Semicircle through Two points” tool Mark point E and F
Click on Segement Between two points>> Draw a line GH	Click on segment Between two Points Mark points G and H A line is drawn
Right click on line GH>>Object properties >>Click on Style>>change Style	Let's change the object properties Right click on line GH Click on Object properties Click on Style change Style
Click on Reflect Object about Line	Select “Reflect Object about Line” tool from the toolbar
Click on the semicircle EF	Click on the semicircle EF This will highlight the semicircle EF
Click on line GH	Click on line GH This will produce the reflected image E'F' on the other side of line GH What does the figure look like now ? It looks like a circle
Click on "Save As" >> type " Line-symmetry " in file name >> click on save	Let us save this file now Click on “File”>> "Save As" I will type the file name as "Line-symmetry" and click on “Save”
	Next, let us learn “Rotate Object around a Point by Angle”
Slide Number 9 Definition of Rotation	Definition of Rotation A rotation is a transformation that turns a figure around a fixed center by an angle If the figure appears unchanged, then the figure has rotation symmetry You can rotate object at any degree measure Rotation can be clockwise and counterclockwise
Click on “File” >> New	Let's open a new Geogebra window click on “File” >> New
Click on “Polygon” tool >> To Construct a Square	Let us construct a square 'ABCD' click on “Regular Polygon” tool from the toolbar
Click on drawing pad and mark points 'A' and 'B'	Click on the drawing pad Mark points 'A' and 'B'
A dialog box opens Click OK	A dialog box opens Click on OK A square 'ABCD' is drawn
Click on Rotate Object around a Point by Angle	Click on “Rotate Object around a Point by Angle” tool
Click on the Square 'ABCD'	Click on the Square 'ABCD' This will highlight the square
Click on the point	Next Click on any one of the vertices I will click on 'A'
A dialog box opens	A dialog box opens
Type "60" in Angle field	Type “60” in the Angle field
Select "°" from first drop down list	Select "°" from first drop down list
Select the option "Clockwise"	Select the option “clockwise”
Click on OK	Click on OK This will rotate the square clockwise at the point of selection with the angle of 60 The rotated image 'A`B`C` 'D' is formed
	Let's move this figure aside using Move tool
	Next, let's “Dilate or enlarge object from point by factor”
Slide Number 10 Dilation	Dilation Dilation or enlargement is a transformation in which a figure is enlarged using a scale factor
Draw a triangle 'ABC'	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>>Mark point 'H'	Click on New point tool and Mark a point 'H'
Click on Dilate Object from Point by Factor tool	Click on “Dilate Object from Point by Factor” tool
Click on triangle 'EFG	Click on the triangle 'EFG' This will highlight the triangle
Click on a point 'H'	Click on the point 'H'
A dialog box opens	A dialog box opens
Type "2">>click OK	Type 2 in the number field Click on OK
	This will dilate or enlarge the object twice
Click on Segement Between two Points >> join points	Click on Segement Between two Points tool 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 number of times as you wish, by typing the value of Factor
Click on "Save As" >> type " Dilate-triangle " in file name >> click on save	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 tutorial
Slide Number 11 Summary	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
Slide Number 12 Assignment	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 in side 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
Show the output of the Assignment	The assignment should look like this
Slide number 13 Acknowledgement	Watch the video available at http://spoken-tutorial.org/ What is a Spoken Tutorial It summarises 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 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 More information on this Mission is available at http://spoken-tutorial.org/NMEICT-Intro This is Neeta Sawant from SNDT Mumbai signing off. Thanks for joining

Contributors and Content Editors

Chandrika, Madhurig