1. What is geometry ?
Geometry (from the Ancient Greek: γεωμετρία; geo- "earth", -metron "measurement") is a branch of mathematics concerned with questions of shape, size, relative position of figures, and the properties of space. A mathematician who works in the field of geometry is called a geometer.

2. Key Words Parallel Perpendicular Perpendicular bisector Angle bisector
Parallelogram
Base
Height

3. Planes
A plane can be thought of as a two-dimensional flat surface, having length and width, but no height. A plane extends indefinitely on all sides and is composed of an infinite number of points and lines. One way to think about a plane is as a sheet of paper with infinite length and width.

4. Basic Geometry Terms Points Points A, B, and C
In geometry, we use points to specify exact locations. They are generally denoted by a number or letter. Because points specify a single, exact location, they are zero-dimensional. In other words, points have no length, width, or height. It may be helpful to think of a point as a miniscule "dot" on a piece of paper.
Points A, B, and C

5. Lines
Lines in geometry may be thought of as a “straight” line that can be drawn on paper with pencil and ruler. A Line is one-dimensional, having length, but no width or height. A line extends indefinitely in both direction.

6. Lines Segments
line segment is a part of a line that is bounded by two distinct end points, and contains every point on the line between its endpoints.

7. Parallel Lines in same plane that never cross or intersect
They are marked using “arrows”

8. Perpendicular Lines that intersect at right angle (900)
They are marked using a small square

9. Perpendicular Bisect Bisect
Bi means “two” sect means “cut”. So, to bisect means to cut in two
Perpendicular bisect
A line that divides a line segment
in half and is at right angles to it.
Equal line segments are marked
with “hash” marks

10. Draw a perpendicular bisector
A bridge over a river needs a perpendicular support under it. Draw the support in the middle of the bridge. (Create using compass, using a ruler and right triangles, and using paper folding.)

11. Angles
An angle measures the amount of turn

12. parallelogram

13. Parallelogram => a four-sided figure with opposite sides parallel and equal in length Base => a side of a two-dimensional closed figure. Common symbol is B Height => the perpendicular distance from the base to the opposite side. common symbol is h

14. area

17. Area of parallelogram
Kris has created a tulip garden in the shape of a parallelogram. he is going to plant 10 tulips per square meter of garden. kris’s garden has a base of 8m and a height of 5m. How much tulip does Kris need?

19. Triangle