# Envelope Command

From GeoGebra Manual

- Envelope[ <Path>, <Point> ]
- Creates the envelope equation of a set of output paths while the moving point is bound to another object.

An envelope is a curve that is tangent to each member of the family of the output paths at some point.

**Example:**The contour of its trace will be the envelope of the ladder. Strictly speaking, GeoGebra computes the envelope of the entire line containing the ladder as a segment. Only such envelopes can be computed where the appropriate construction leads to an algebraic equation system.

**Note:**See also Locus, LocusEquation commands and GeoGebra Automated Reasoning Tools: A Tutorial.