It is called a perpendicular bisector.
It is perpendicular line segment
It is perpendicular line segment
Perpendicular Bisector
It is a perpendicular bisector line
It is a perpendicular bisector line
No, a segment is not necessarily perpendicular. A segment is simply a straight line connecting two points. A perpendicular segment would be a segment that forms a right angle with another segment or line.
It is called a "side" (in polygons, these may be called edges, but this can cause confusion with the term as used in 3-dimensional solids).
hypotenuse
An altitude.
It is called an arm of the angle.
It is called a side or edge.
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