Geometry Expressions is the world’s first Interactive Symbolic Geometry System.

This means:

Geometric figures can be defined by either Symbolic Constraints or numeric locations.
Measurements on your drawing are not only presented numerically, but also expressed symbolically as Mathematical Expressions.
Your drawing comes to life via parametric, symbolic animation.
All the usual constructions are available but also powerful, new symbolic constraints.

Geometry Expressions can be used as a stand-alone program or in conjunction with your favorite algebra system via MathML input and output.

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Geometry.Expressions.v1.0.34.sh.rar