1. Introduction to
Geometry
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2. What does Geometry Mean?
Gee – I’m – A- Tree
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This Photo by Unknown Author is licensed under CC BY-NC-ND

3. line
Line Segment
Points/Planes
Collinear Points
Rays
What you will learn

4. Geometry
Relates to shape, size, position of figures, and the properties of space.
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5. What is the point?
On the right we have 2 points, labelled A and B.
There is only one straight line that passes through the points A and B.
We call that the line AB
The line AB goes on forever in both directions. A B
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6. The line can be named with a single lowercase letter like l, m, or n.
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7. Line Segment
A line beginning at the point A and ending at the point B is called a line segment.
It is wrote as [AB] A B
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8. Spot the difference between Line Segment and line
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9. Rays A line that has a start point but no end point.
A line that starts at A and continues on through B is called the ray [AB
Rays are sometimes called half-lines
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10. Collinear Points If the points are in the same straight line
They are called collinear
The points C, A, B and D are collinear
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11. The plane
The flat surface on which points and lines are shown is called a plane.
A plane contains an infinite number of points.
This diagram shows five points drawn on the plane of the page.
The points D, A and E are collinear
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12. Summary Points Line AB Line Segment [AB] Ray [AB Collinear Points
Plane
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