GEOMETRY

B Y MI S

S O.

GEOMETRY (JEE-OM-I-TREE) – N.

The branch of mathematics concerned with the properties of and relationships between points, lines, planes, and figures.

GEOMETRY IS ANCIENT.The earliest records of geometry

can be traced to ancient Egypt and the Indus Valley from around 3000 BC.

EUCLIDEuclid, a Greek mathematician,

wrote The Elements of Geometry.

He presented geometry in a practical form known as Euclidean geometry Euclid’s was not the first important early texts on geometry.

POINTAn exact location in space; named

by a capital letter

LINEA straight path that extends

forever in opposite directions; named by two points on the line

RS

R

S

LINE SEGMENTA part of a line with two

endpoints; named by the two endpoints

PZ

ZP Q

PLANEA flat surface that extends without

end in all directions

RAYA part of a line with one endpoint

that extends forever in one direction; named by the endpoint first followed by another point on the ray

ANGLETwo rays joined at a common

endpoint called the vertex; named by the vertex or the vertex and a point on each ray

VERTEXThe point on an angle or polygon

where two lines or rays meet; named with a capital letter

Vertex

RIGHT ANGLE

90 degreesSquare cornerLittle box

ACUTE ANGLELess than 90 degrees

OBTUSE ANGLEMore than 90 degrees

STRAIGHT ANGLE180 degreesStraight line

http://www.youtube.com/watch?v=yptZt9hwrzU&safety_mode=true&persist_safety_mode=1&safe=active

ACTIVITY 1Build all 4 angles with your bodies on the carpet. Each group

will have 4 students in it.

Miss O. will come around to take a photo of each angle for the website!

ACTIVITY 2Play “Simon Says” with each hand motion that represents a

geometric term we learned today!

INTERSECTING LINESLines that pass through the same

point

PARALLEL LINESLines that never intersect

PERPENDICULAR LINESLines that form right angles (90

degree angles)All perpendicular lines are also

intersecting lines!

WHAT GEOMETRIC TERM IS REPRESENTED?

WHAT GEOMETRIC TERM IS REPRESENTED?

WHAT GEOMETRIC TERM IS REPRESENTED?

WHAT GEOMETRIC TERM IS REPRESENTED?

WHAT GEOMETRIC TERM IS REPRESENTED?

WHAT GEOMETRIC TERM IS REPRESENTED?

WHAT GEOMETRIC TERM IS REPRESENTED?

WHAT GEOMETRIC TERM IS REPRESENTED?

WHAT GEOMETRIC TERM IS REPRESENTED?

WHAT GEOMETRIC TERM IS REPRESENTED?

WHAT GEOMETRIC TERM IS REPRESENTED?

TALK AND TURN: In the world around you, where do you see geometric figures in

real life every day?Make a list with your partner of at least 3 ways!

FIND ALL THE ANGLES