Points, Lines & Planes Segments, Rays & Distance: Alg1a/geoma 1-2 1-3

Points, Lines & Planes Segments, Rays & Distance Alg1A/GeomA 1-2 1-3

Warm Up 

In your groups, define the following terms:    

Point Line Plane Space

1-2 Terms & Definitions 

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Collinear points are points all contained in one line. Coplanar points are points all in one plane. The intersection of two figures is the set of all points shared by both figures.

What is the intersection of 2 lines? What is the intersection of 2 planes?

Example In your groups answer the following: QuickTimeª and a TIFF (Uncompressed) decompressor are needed to see this picture.

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Name 2 points collinear

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Name 2 pts non-collinear

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Name the intersection of plane M and line j

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Name 2 pts coplanar and 2 pts non-coplanar

Ex. 2 Draw 2 planes intersecting, one vertical (Plane N) and one horizontal (Plane M). Include the following in your picture:

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The two planes intersect at line XY Line b lies on plane M and intersects line XY at point A Point P is coplanar to Point A on plane N

Did you get this?

QuickTimeª and a TIFF (Uncompressed) decompressor are needed to see this picture.

Ex. 3 

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QuickTimeª and a TIFF (Uncompressed) decompressor are needed to see this picture.

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Name 2 planes that intersect AB Name 2 parallel planes Name 2 Perpendicular Planes

1-3 Terms & Definitions 

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Segment AC, written AC, consists of the points A and C and all the points between A and C. A and C are called the endpoints of AC. uuur Ray AC, written AC , consists of AC and other points P suchuuu that r C is between A and P. The endpoint of AC is A, the point named first. Opposite Rays share an endpoint and have opposite directions

Postulate 

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Postulate - statement that is accepted without proof Segment Addition Postulate: If B is between A and C, then AB + BC = AC s uur between means B is on the line AC and in between A and C.

Ex. If F is inbetween E and G with EF = x and FG = x+6 and EG = 24 a. Find x

b. Find FG

Congruent:   

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Congruent – same size and shape Congruent segments – segments with equal length Congruent angles – angles that have the same measure Midpoint of a segment is the point that divides the segment into two congruent segments. Bisector of a segment – is a line, ray, segment, or plane that intersects the segment at its midpoint.

True or False Draw suur the following: suur AB bisects DE at point C

Questions: 1. DC ≅  2. AC ≅  3. C is the midpt of DE 4. C is the midpt of AB 5. DE +  =  6. B is inbtwn D and E