Constructing Parallel and Perpendicular Lines Geometry 3-7

Draw a line and a point on a piece of patty paper Investigation

Investigation Fold a perpendicular through the point Mark the line, what are the four angles? Investigation

Fold another line perpendicular to the folded line, and through the point Investigation

Investigation How could we check that the lines are parallel Use the first folded line as a transversal, and check corresponding angles Investigation

Constructing Parallel Lines Investigation

Draw a line and a point not on the line on a sheet of printer paper Try to construct a parallel line through this point with a compass and a straightedge Investigation

How To Construct Parallel Lines Begin with point P and line k. How To Construct Parallel Lines Draw an arbitrary line through point P, intersecting line k. Call the intersection point Q. Now the task is to construct an angle with vertex P, congruent to the angle of intersection. P k Q Investigation

Center the compass at point Q and draw an arc intersecting both lines Center the compass at point Q and draw an arc intersecting both lines. Without changing the radius of the compass, center it at point P and draw another arc P k Q Investigation

Set the compass radius to the distance between the two intersection points of the first arc. Now center the compass at the point where the second arc intersects line PQ. Mark the arc intersection point R. P k Q R Investigation

Line PR is parallel to line k Q Investigation

Review Lesson 1-5

How to construct a perpendicular to a line through a specific point?

How to construct a perpendicular to a line through a specific point? Now, create a bisector from these points Perpendicular

Perpendicular

Perpendicular

Perpendicular

Perpendicular

Worksheet 3-8 All Homework