4
Three pairs. The line joining the midpoints of any two sides of a triangle is always parallel to the third side of the triangle (and half its length).
There is no specific name - other than what you used: "a pair of parallel line segments".
A circle.
They are equal line segments that meet at an angle of 135°.
First, lines and rays cannot be congruent because they do not have both end points defined. Not having an end point define means we cannot talk about their length so they can't be congruent. Line segments, however, can be congruent. Congruent line segments NEED NOT be parallel.Furthermore, if two line segments are parallel, that does not mean they are congruent since parallel line segments may not have the same length.Congruent line segments would be ones that are the same length.
how many pairs of parallel line segments does a stop sigh have
NoneOctagon hasn't got any pairs of parallel line
rectangle, octagon, hexagon
A quadrilateral with 2 pairs of parallel line segments is a parallelogram. Parallelograms include rectangles, rhombuses, and squares.
Pair of radii
A regular hexagon has three sets (pairs) of parallel line segments that form it.
Many polygons, such as squares, rectangles, rhombi, parallelograms, etc. have more than 1 pairs of parallel line segments. Trapezoids have only 1 pair of parallel line segments. These few shapes are just quadrilaterals, other polygons also have more than 1 pair of parallel line segments (e.g. regularhexagons, octagons, etc.). Triangles never have any parallel line segments.
No
A square has two sets of parallel line segments. "Parallel" does not describe a square, however.
They can not be line segments on the same line, but they can both be line segments.
An 8 sided octagon has 8 line segments which are its 8 sides
8 of them because an octagon is an 8 sided polygon