MOODLE DAY

Agenda:-Check Homework

-Warm-Up-Notes “4.5 A Continued”

Quiz Monday

Warm-up ~ Graph Each on the same graph

1. y = -3x + 5

Graphing methods

• make a table – works for all

• x and y intercepts: best for ax + by = c

2. 2x + 3y = 12 3. y = 3/4x - 5

1. y = -3x + 5 Strategy:

Make a table x y

-1 8

0 5

1 2

Strategies:

Make a table

OR

X intercept (6, 0)

Y intercept (0, 4)

x y

-3 6

0 4

3 2

2. 2x + 3y = 12

Strategy:

Make a table x y

-4 -8

0 -5

4 -2

3. y = 3/4x - 5

Turn to a graph page in your vocabulary book.

Rule:

Characteristics:

Common Mistakes:

Example:

Linear

Equation- An equation of a line

Standard form

Slope-intercept form

ax + by = c 2x + 3y = 1

y = mx + b y = 3x + 1

x intercept:

y intercept:

Where it crosses the x axis

Where it crosses the y axis

(x, 0)

(0, y)

Horizontal line:

Vertical line:

y = #

x = #

x-int

y-int

LINEAR:

y = 2x – 5

x = -7

3x – 4y = 20

Linear Equations SummaryNo need to write these down, they’re just review of what you just wrote…

• an equation whose graph is a straight line

• only has one or two variables

• no exponents higher than 1

• variables do not multiply or divide each other

Not LINEAR:y = 2x2 – 5 xy = -73x – 4y + z = 20

Example 1: Linear or Not Linear?

3m + 2n = 12 Yes!

x2 + y = 10 No!

y = 1/3 x + 12 Yes!

xy = 6 No!

y = 6

x

No!

Standard Form

A linear equation in the form Ax + By = C

A, B and C are integers (not fractions) with a GCF of 1. A must be positive

Example: 3x – 5y = 10

A = 3 B = -5 C = 10

More vocabNow try filling out a “web” on your own

A linear equation in the form y = mx + b, where m is the slope and b is the y-intercept

Ex: y = 3x + 4

slope = 3

y-intercept = 4

Slope – Intercept Form

More vocabNow try filling out a “web” on your own

A linear equation in the form y = mx + b, where m is the slope and b is the y-intercept

Ex: y = 3x + 4

slope = 3

y-intercept = 4

Slope – Intercept Form

More vocabNow try filling out a “web” on your own

up 4

A linear equation in the form y = mx + b, where m is the slope and b is the y-intercept

Ex: y = 3x + 4

slope = 3

y-intercept = 4

Slope – Intercept Form

More vocabNow try filling out a “web” on your own

up 4

up 3

A linear equation in the form y = mx + b, where m is the slope and b is the y-intercept

Ex: y = 3x + 4

slope = 3

y-intercept = 4

Slope – Intercept Form

More vocabNow try filling out a “web” on your own

up 4

up 3

Over 1

Horizontal Line has an equation y = # The coordinate at which the graph intersects the Y-axis

When x = 0. ( 0, ? )

Vertical Linehas an equation x = # The coordinate at which the graph intersects the X-axis

When y = 0. ( ? , 0 )

“Straight Lines”

29. y = 2x - 8 31. y = x – 6

Homework Solutions, p. 221

35. x + 3y = 9 36. 4x + 6y = 8

Homework Solutions, p. 221

Section 4.5 A Continued

Objective for today: Learn how to graph using Slope-Intercept form.

In your notes: (on back)Ex. 3: Use slope intercept form

• works for y = mx +by = -5x + 4

y = 1x -73

m = ____

b = ____

m = ____

b = ____

Identify the slope and y-intercept

-5

4

1/3

-7...

Plot the y-intercept (0, b) slope (m): vertical change then horizontal change

+

-- +

. ..

In your notes: (on back)Ex. 3: Use slope intercept form

• works for y = mx +b

y = 3x + 4

y = -2x -2 3

m = ____

b = ____

m = ____

b = ____

Identify the slope and y-intercept

Your Turn:

Plot the y-intercept (0, b) slope (m): vertical change then horizontal change

3

4

-2/3

-2

Did you master today’s objective?

x + y = 10

What is the best way to graph the given line?

Make a table or x and y intercepts

y = 3x + 6

Choices:

Make a table, x and y intercepts, slope intercept form

Slope intercept form