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Plane figures: FAQ

Frequently asked questions about plane figures.

What's the difference between a line and a line segment?

A line goes on forever in both directions, while a line segment has two endpoints.
Try it yourself with this exercise:

What are the different types of angles?

There are three main types of angles: acute (less than 90, degrees), right (90, degrees), and obtuse (more than 90, degrees).
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What is the difference between parallel and perpendicular lines?

Parallel lines are two or more lines that never intersect, no matter how far they are extended. They always maintain the same distance from one another.
Perpendicular lines, on the other hand, are two lines that intersect at a right angle (90 degrees). So, while both terms refer to the relationship between two lines, they are different relationships.
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How can I tell if a shape has line symmetry?

If you can draw a line through the shape and the two halves match up exactly, the shape has line symmetry.
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Where do we use the concepts from this unit in the real world?

There are countless applications! For example, architects use the concepts of parallel and perpendicular lines when designing buildings, and artists use symmetry to create balanced and aesthetically pleasing works.

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