construct geometry objects

I need a little help with the construction of geometric shapes.
For example, how can I draw the lines of a triangle that I only know the lengths and/or angles of? Is there a shortcut to transfer the line length or the angle?

Draw the first line with the known length. Draw a circle with a radius like the length of the second line, centered at the one end of the first line. Then draw a circle with a radius like the length of the third line, centered at the other end of the first line. The intersection point of the circles is the missing corner.



But you can not simply edit the values of an existing triangle.

Another alterative using 1 base line with a known length and 2 angles :
- draw the base line
- use the tools/line/angle feature : in the tool option bar select the appropriate angle (say 30°) and choose a length (say 100)

- use the tools/line/angle feature : in the tool option bar select the appropriate angle (say 160°) and choose a length (say 100)

- Use trim or lengthen function to cut or extend the lines if necessary.

More details on drawing features at : https://librecad.readthedocs.io/en/latest/ref/tools.html. Note : this document is being "reworked".