You do not have to do anything!
Actually it really is called an edge!
A ruler has markings, a straight edge does not. In "straight edge and compass" constructions, you are not allowed to mark the straight edge. Things that are impossible using only a straight edge and compass are possible if markings are allowed (for example, it's possible to trisect an angle using a marked straight edge).
A perpendicular edge is a side of a plane shape that is at right angles (90 degrees) to another edge.
The line round the edge of the circle.
You do not have to do anything!
Actually it really is called an edge!
A Ruler
The length of the edge of a circle.
A ruler has markings, a straight edge does not. In "straight edge and compass" constructions, you are not allowed to mark the straight edge. Things that are impossible using only a straight edge and compass are possible if markings are allowed (for example, it's possible to trisect an angle using a marked straight edge).
A perpendicular edge is a side of a plane shape that is at right angles (90 degrees) to another edge.
The line round the edge of the circle.
A segment is part of a circle created by drawing a line from a point on the edge to another point on the edge.
Generally a ruler is a straight edge, but it can be anything... I generally just use a spare pencil.
ask ur math teacher ;)
A straight edge is basically another name for a ruler, or it could be anything that makes straight lines.
An edge is a straight line as part of a polygon. It can also be the straight line joining two faces of a solid which has polygonal faces.