How old do you have to be to become a emergency doctor and a paramedic?

Line segment- a portion of a line with two endpoints.

Ray- a line with an initial endpoint and then extends infinitely.

Opposite rays- two rays that have the same initial point and extend infinitely in opposite directions in a straight line.

Parallel lines- lines that don't intersect

Collinear- two or more points that lie on the same line.

Coplanar- three or more points that lie in the same plane.

Plane- a flat surface that consists of at least three noncollinear points.

Angle bisector- a ray that divides an angle into two angles that are congruent.

Midpoint- a point that divides a segment into two congruent segments.

Perpendicular lines- two lines that intersect to form a right angle.

hope this helps! :-)