What lies behind us and what lies before us are tiny matters compared to what lies within us.

Ralph Waldo Emerson

Today:• Return C3 Tests• Progress Reports• Goal Evaluations• 4.1 Instruction -

Notes• Practice

Algebra

The Coordinate Plane

Objectives:1. Plot points in the coordinate plane.2. Plot points in Real World problems. Vocabulary: coordinate plane, origin, x-axis, y-axis, ordered pair, x-coordinate, y-coordinate, quadrant, scatter plot

4.1

horizontal

or x-axis

vertical or y-axis

origin(0, 0)

1 2 3 4 5 6 7

123

56

4

7

-6

-2

-4

-6-4 -2

Vocabulary: coordinate plane – a plane with an x-axis and a y-axis that intersect at the

origin.

ordered pair – the location of any point on a coordinateplane using two numbers (x-coordinate, y-coordinate)

Vocabulary: coordinate plane

ordered pair

A(4, 3)

B(3, -1)

C(-3, 3)

D(-6, -3)

AC

BD

The Coordinate Plane4.1

Vocabulary: coordinate plane – a plane with an x-axis and a y-axis that intersect at the origin.

ordered pair – the location of a any point on a coordinateplane using two numbers (x-coordinate, y-coordinate)

quadrant – the 4 regions of the coordinate plane

1 2 3 4 5 6 7

123

56

4

7

-6-4 -2

Vocabulary: coordinate plane

ordered pair

quadrant

III

IVIII

(–,+)

(+,+)

(+,–)

(–,–) -6

-2

-4

The Coordinate Plane4.1

Identify Coordinates1Example

Find the ordered pair of the points.

(2, 2)

(-4, 5)

(7, -4)

(-3, -2)

(7, 0)

1 2 3 4 5 6 7

123

56

4

7

-6-4 -2

-6

-2

-4

(1, -6)

(-5, -6)

(-7, 2)

(6, 7)

(4, -3)

I

II

IV

III

None

IV

III

II

I

IV

Plot Coordinates2Example

Plot the ordered pair on the coordinate plane

(3, 5)

(-1, -5)

(7, 4)

(-3, 2)

1 2 3 4 5 6 7

123

56

4

7

-6-4 -2

-6

-2

-4

(3, -6)

(-5, -2)

(3, -4)

(-6, 0)

I

III

I

II

IV

III

IV

none

The Coordinate Plane

Steps to Make a Scatter Plot:1. Determine what will be x and y.

I. x – is in charge, it changes automatically

II. y – depends on x, is not automatic2. Determine units of each axis and label.

I. Find range of variableII. Divide range by number of squaresIII.Always round up to “nice” unit

3. Plot points.

4.1

Make a Scatter Plot3ExampleThe age (in years) of seven used cars and the price (in thousands of dollars) paid

$8,800

0 1 2 3 4 5 6 78 9 1011 121314150

1234

56

78910

1112

131415

age of carp

rice

in

$1

,00

0

Age 4 5 3 5 6 4 7

Price6.9

6.1

7.5

5.2

4.2

7.1

3.0

for the cars are recorded in the table. Make a scatter plot and explain what it indicates.

How much would a 2-year old car cost?

Make a Scatter Plot4ExampleThe age (in years) of seven used cars and the price (in thousands of dollars) paid

$1,500

0 1 2 3 4 5 6 78 9 1011 121314150

1234

56

78910

1112

131415

Age 4 5 3 5 6 4 7

Price69

61

75

52

42

71

30

for the cars are recorded in the table. Make a scatter plot and explain what it indicates.

How much would a 9-year old car cost?

pri

ce in

$1

,00

0age of car

Make a Scatter Plot3ExampleThe amount (in millions of dollars) spend in the United States on snowmobiles is shown in the table. Make a scatter plot and explain what it indicates.Year 90 91 92 93 94 95 96

Spent322

362

391

515

715

924

970

0

100

500

1000

1500

Am

ount

spent

(mill

ions

$)

90 95 00 05

year

Make a Scatter Plot3ExampleWhat do you predict was spent in the year 2000?

$1,600,000,000

0

100

500

1000

1500

Am

ount

spent

(mill

ions

$)

90 95 00 05

year

Year 90 91 92 93 94 95 96

Spent322

362

391

515

715

924

970

Assignment4.1

Assignment:• 4.1 p206 #10-29,

35-37 - USE GRAPH PAPER

• C3 Progress Report

What lies behind us and what lies before us are tiny matters compared to what lies within us.

Ralph Waldo Emerson

Assignment4.1

Assignment:• 4.1 p206 #10-29,

35-37 - USE GRAPH PAPER

• Graph Picture• C3 Progress

Report

What lies behind us and what lies before us are tiny matters compared to what lies within us.

Ralph Waldo Emerson

Graph a Picture5Example

Plot the points to graph a picture.