Construct a Parallel Line

In geometry, once you learn how to do one construction, you can use that as one step in a larger construction. For instance, two parallel lines are both perpendicular to the same line. So, if you have a line AB, you can construct a new line DE that is parallel to AB as follows. First, construct a line CD that is perpendicular to the original line AB. Then construct a line DE that is perpendicular to line CD. Now line DE is parallel to line AB. No matter how long you draw lines AB and DE, they will never cross.
Construct a Parallel Line

Information: Construct a Parallel Line