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POINTS, LINES AND PLANES

Section 1-1

Jim Smith JCHS

What is Geometry?

- Geometry is the study of shapes
- They studied Geometry in Ancient Mesopotamia

Ancient Egypt - Geometry is important in the art and construction

fields

POINT

- A POINT is an exact location on a graph, shape

or in space. - The ball is a POINT on the line.

LINE

- A LINE goes in opposite directions and never,

ever ends.

Take a pearl necklace and stretch it out. The

pearls are like points on a line.

PLANE

- A PLANE is a flat surface that goes on forever

in all directions. - Imagine sitting on an island in the middle of

the ocean. No matter which way you lookall you

see is waterforever.

TO NAME A POINT- WE USE A CAPTIAL LETTER

- .A
- .X

TO NAME A LINE- USE ANY 2 POINTS ON THE LINE

- LINE RT or LINE ST or LINE RS

RT

RS

POINTS ON THE SAME LINE ARE CALLED COLLINEAR

POINTS

- A, B, AND Y ARE COLLINEAR

.

.

Y

.

B

A

TO NAME A PLANE WE USE 3 OR 4 NONCOLLINEAR POINTS

- PLANE WAG or XAG or WXA

.

.A

Q

X

.W

.G

PLANES CAN BE NAMED USING 1 LETTER . PLANE Q

THE INTERSECTION OF 2 LINES IS A POINT

s

S IS THE INTERSECTION OF THE 2 LINES

LINE AB IS CONTAINED IN PLANE Q

Q

B

A

LINE XY INTERSECTS PLANE Q AT POINT X

Y

Q

.

X

THE ARROW INTERSECTS THE TARGET AT 1 POINT

Lines YB and XZ do not intersect

Z

.

Y

.

B

X

THE INTERSECTION OF 2 PLANES IS A LINE

A

D

G

B

C

E

E

G

H

C

F

POINTS AND LINES CONTAINED IN THE SAME PLANE ARE

CALLED COPLANAR