This assignment does not rely on the usual basic construction tools that are represented by icons above the construction windo. Instead, you will use a macro: a routine defined by the user. Macros can be used to easily repeat very complicated constructions.
In this construction window, a macro for reflecting a point in a line has already been created for you. You will use this macro to reflect the entire triangle.
> NOTE macros are always evoked by right-clicking an empty portion of the construction window, then selecting the name of the macro in the dialog box that appears..

 

Reflect the three vertices of the triangle in the given line as follows:

  • First, right click anywhere in the construction window and select the macro "Reflect a point in a line". 
  • Below the construction window you will see the words "Macro reflection in a line: 1.Line - Line of reflection." These instructions indicate that the macro requires you to select a line, which will be the line of reflection. 
  • Click the reflection line below the black triangle.
  • Below the construction window note the words "Macro reflection in a line: 2.Point - Point to be reflected."  
  • Click any of the points of the original triangle. A dot should appear reflected across the line.
  • Below the construction window, the words "Macro reflection in a line: 1.Line - Line of reflection." should reappear. This means that you are ready to reflect another point (you don't need to right click again to re-select the macro)
  • Reflect the other two triangle points one after the other, by first selecting the line of reflection and then selecting the point to be reflected.
  • A “Well Done!” screen should appear when you have correctly reflected all three points.

In general, the reflected triangle will respond appropriately when the points of the original triangle are moved, and when the line of reflection is moved. You can see how this works here.

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