SpaTools: Construct Triangle with three known sides

Last week, I was trying to teach my son some basic concepts of elementary geometry to solve some homework questions. One of the question was about “Construct a triangle with three known sides”.

 

 

I still remember the days of high school when we used to construct triangles of three known sides using ruler and a drafting compass. Certainly, it was fun and so interesting to make the shapes using Ruler, Compass and set square.

 

 

Though I am not good at teaching and teaching is not an easy job but tried my best to make him learn conceptually. The effectiveness of my teaching will be revealed by grading from school after exam.😊

However, during teaching him, I got an idea to develop a jig in AutoCAD to construct a triangle of three known sides.

Conventionally, the same procedure (Ruler & Compass) is used in AutoCAD to construct the triangle. Two different circles are drawn centered at the ends of the line segment. The ends of the line segment are then to be  connected with the intersection of the two circles to form the triangle as depicted below:

 

 

To simplify this procedure, I have developed a tool to construct a triangle when the length of the all sides is known.  Enter “TRIANG” on command prompt to invoke the command. Specify the length of first side by clicking on ends of the line segment and then the lengths of second and third side as demonstrated below:


Obviously, the circles will intersect twice with each other, so the resulting triangle can have two variants.

The exceptional case is when both circles do not intersect which implies that the length of the second or/and third side is invalid.

 

The updated SpaTools DLL can be downloaded from Cadomation.

 

  


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