Segments, Rays, Parallel Lines, and Planes Section 1.4 Segments, Rays, Parallel Lines, and Planes

1-4 Segments, Rays, Parallel Lines, and Planes Objectives / “I can…” Define line segments and rays Properly name line segments and rays Identify parallel lines and skew lines

Ch 1-4: Segments, Rays, Parallel Lines & Planes Line Segment is part of a line that has a beginning and an end (called endpoints). named using both endpoints and w/ a little segment on top AB or BA A B

Ray Is part of a line that has a specific starting point and goes forever in one direction. Name a ray starting with the endpoint. (The 2nd letter tells which direction to go.) Put a small ray symbol over the letters. DE or D E F DF

Rays, continued Are these two rays the same? B AB A B A BA No Different endpoints Extend in different directions

Opposite Rays are 2 collinear rays with the same endpoint. they form a line R O B I N BR & BN are opp. rays

Parallel Lines ~ coplanar lines that do Lines that do not intersect may or may not be coplanar. Parallel Lines ~ coplanar lines that do not intersect Skew Lines ~ noncoplanar They are not parallel & they do not intersect Same direction & Same plane Different direction & Different plane

Hint: Parallel lines – same direction same plane Skew Lines – different direction different plane

Parallel to GJ? Skew to GJ? HI, DN AB, CD, CH

Parallel Planes Parallel planes are planes that never intersect Example: the purple planes in the above illustration A line and plane that never intersect are also parallel

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