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Transformation in GSP
This page focuses on the use of transformation tools. Viewlets are provided to demonstrate the constructions in the first file. Some pages of the first file are converted into Java applets and can be opened directly in the web browser.

Transformation and Symmetry
The 'Transform' menu provides tools for performing and exploring transformation (translation, reflection, rotation and dilation) of 2D figures. Sometimes these tools can be useful means, and even shortcuts, for constructing geometric objects.
translation by a marked vector: specify a vector by selecting its endpoints on screen or entering numerical values for its components
reflection by a marked mirror (line or line segment)
rotation by a marked center and angle: specify an angle by entering its size (fixed angle) or selecting the 3 vertices that define an angle (the angle could be then controlled through the mouse)
rotation by a hidden marked angle
dilation by a marked center and ratio: the ratio can be specified by entering numerical values or selecting 3 points on a straight line (e.g. to mark the ratio AB to AC, select the points in the order A, C, B.)
another way to demonstrate translation
construct a polygon with 3 axes of symmetry
construct a polygon with rotational symmetry of order 3
rotate the image of a figure to check its symmetry
reflection of a point about a line in the coordinate plane; compare coordinate of the original point and the image
drawing and checking reflection of a polygon about a line, working on a dotted square grid