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Classification of Angles and Lines

Grade 9
Sep 12, 2022

Parallel Lines 

Look carefully and identify if the railroad tracks intersect each other. 

Parallel Lines Classification of Angles and Lines

The railroad tracks do not intersect each other at any point. The lines that lie in the same plane, do not intersect each other, and are always the same distance apart are called parallel lines

parallel lines

Parallel Postulate 

Consider a line m and plot a point P outside the line. We can draw only one line parallel to the given line passing through the point. 

Parallel Postulate 

So, m′ is parallel to m and passes through P.

Skew Lines 

The lines that do not intersect each other but lie in different planes are called Skew lines. 

Skew Lines 

Perpendicular Lines 

The lines which intersect each other at 90° are called perpendicular lines. 

Perpendicular Lines

Perpendicular Postulate 

Consider a line m and plot a point P outside the line. 

We can draw only one line perpendicular to the given line passing through the point. 

Concept Map

Concept Map: 


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