Lesson 8
1. Lesson 8
1.4. Explore
Module 2: Logic and Geometry
Explore
The strategies used to construct and then verify that lines are parallel in a design will vary. For instance, different strategies could be used to construct parallel lines on a blanket versus parallel lines in a corn maze.
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When Jarjeet was asked to construct a set of parallel lines for his T-shirt logo in Try This 1, he decided to use a compass and a ruler. At this time, type the keywords “constructing a parallel through a point” into your favourite Internet search engine. This search should take you to a page at the Math Open Reference website.
This strategy works by using the corresponding angles property. Recall that when a transversal intersects two parallel lines, it creates pairs of corresponding angles that are equal in measure. In this strategy, two equal corresponding angles are created first with the compass. These angles are then used to identify the location of line RS. Using the ruler or straightedge to draw a line through points R and S creates the line that is parallel to the original line—line PQ.
Self-Check 1
- Complete “Practising” question 4 on page 85 of your textbook. You may find it helpful to review Parallelogram. Answer
- Complete “Practising” question 6 on page 79 of your textbook. Answer