Drawing rays, lines, and line segments

The topic  appears under the 7th Grade Math Mission. This exercise introduces the words ray, line and segment with visual models and definitions.

Types of Problems
There is one type of problem in this exercise:


 * 1) Create the picture and answer the question: This problem has two parts. First of all the student is asked to use the manipulative to create a picture. They are also asked to select two answers from drop-down lists about the objects drawn in the picture.Drlals1.png

Strategies
One-dimensional geometry vocabulary is the most relevant knowledge for this exercise, in particular the concepts of ray, line and segment.
 * 1) A line is the fundamental one-dimensional object. It has no endpoints and extends infinitely far in two directions.
 * 2) A ray is part of a line. It has one endpoint and extends infinitely far in one direction.
 * 3) A line segment (or just segment) is part of a line. It has two endpoints and extends infinitely far in zero directions. It is the only one of these concepts that has a measurement, or length.
 * 4) When constructing the picture it is necessary to be careful as sometimes non-parallel lines are close to enough to appear parallel if they are not looked at carefully.