Identifying Rays

Geometry

Introduction to Euclidean geometry

Euclid as the Father of Geometry
Language and Notation of Basic Geometry
Lines, Line Segments, and Rays
Measuring segments
Points, lines, and planes
Identifying Rays
Recognizing rays lines and line segments
Congruent segments
Segment addition
Midpoint of a segment
Language and Notation of the Circle
The Golden Ratio

Identifying Rays Identifying Rays

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Identifying Rays

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Identify all the rays shown in the image below.
and this is a reminder what a ray is.
A ray start at some point and then goes on forever in some direction.
In order to find a ray you need that point that you're starting off on
so let's that point over there is called X
and then you need another point that sits on the ray
and the ray is just keep going beyond, we
will name that point as "Y" and we will call the ray "XY"
It starts in "X" and keeps going in the direction of "y"
for ever, it crosses "y" and keeps going further
we need the second point to specify the direction
in which the ray is going.
So, lets identify all the rays shown in the image
below, we can start anywhere, we will start at
point J, the only line segment we have starting from J
is JH going up, goes upto H and keeps on going
in that direction beyond H, ray JH, starting from J
going through H and going beyond it forever
now if we go to H, there is no ray HJ as the line ends
in J and does not keep going beyond J, there is no
ray H as it is just one point, just usiing one point,
we cannot say it as a ray. now looking at our diagram
the only ray is JH. Now let us look at the other points.
If we look at point C, once again there is no point
after C to specify it as a ray, we can have a ray CE,
starts at C goes through E and goes on for ever,
you can also have a ray starting at C, going through F
and going on forever, CE & CF are the same rays
as F sits on ray CE and E sits of ray CF,
so CE & CF are the same rays,
now lets think about what we can do from point E,
We can start at point E , go in the direction of C
and go beyond C, so it is a ray, ray EC
you could start in E and go in the direction of A and go
beyond A, so EA is a ray, and we can start at E and
go in the direction of F and go beyond F, that is ray EF
ray EF and ray CF are different as the
starting points are different
Now lets go to point F. To the left of point F
there is no other point. We can look at the right,
we can have ray FE, start at F go through E and
beyond E, you can have ray FC, start at F
go through C and beyond C that is teh same thing as FE
ray FE and ray FC are the same as the point E
is on ray FC, then finally we have not focussed on point A
you may think there is ray AE, but the line does not
go beyond E, so it is not a ray, to the top of A
there is no other point, so there is no ray there either
that is all the rays based on the points specified.
If they had given us a point over there, we could have
had other rays,

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