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OBJECTIVES:

1. Write an equation of a line, given its slope and y-intercept. 2. Graph a line, using its slope and y-intercept. 3. Write an equation of a line, given its slope and a point on the line. 4. Write an equation of a line, given two points on the line. 5. Write an equation of a line parallel or perpendicular to a given line. 6. Write an equation of a line that models real data.

1. Write an equation of a line, given its slope and y-intercept. 2. Graph a line, using its slope and y-intercept. 3. Write an equation of a line, given its slope and a point on the line. 4. Write an equation of a line, given two points on the line. 5. Write an equation of a line parallel or perpendicular to a given line. 6. Write an equation of a line that models real data.

1.
Copyright © 2010 Pearson Education, Inc. All rights reserved

Sec 4.3 - 1

Sec 4.3 - 1

2.
Chapter 4

Graphs, Linear Equations,

and Functions

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Sec 4.3 - 2

Graphs, Linear Equations,

and Functions

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Sec 4.3 - 2

3.
4.3

Linear Equations in Two

Variables

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Sec 4.3 - 3

Linear Equations in Two

Variables

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Sec 4.3 - 3

4.
4.3 Linear Equations in Two Variables

Objectives

1. Write an equation of a line, given its slope and y-

intercept.

2. Graph a line, using its slope and y-intercept.

3. Write an equation of a line, given its slope and a

point on the line.

4. Write an equation of a line, given two points on

the line.

5. Write an equation of a line parallel or

perpendicular to a given line.

6. Write an equation of a line that models real data.

Copyright © 2010 Pearson Education, Inc. All rights reserved. Sec 4.3 - 4

Objectives

1. Write an equation of a line, given its slope and y-

intercept.

2. Graph a line, using its slope and y-intercept.

3. Write an equation of a line, given its slope and a

point on the line.

4. Write an equation of a line, given two points on

the line.

5. Write an equation of a line parallel or

perpendicular to a given line.

6. Write an equation of a line that models real data.

Copyright © 2010 Pearson Education, Inc. All rights reserved. Sec 4.3 - 4

5.
4.3 Linear Equations in Two Variables

Write an equation of a line given its slope and y-intercept.

Given the slope m of a line and the y-intercept b of the

line, we can determine its equation.

Copyright © 2010 Pearson Education, Inc. All rights reserved. Sec 4.3 - 5

Write an equation of a line given its slope and y-intercept.

Given the slope m of a line and the y-intercept b of the

line, we can determine its equation.

Copyright © 2010 Pearson Education, Inc. All rights reserved. Sec 4.3 - 5

6.
4.3 Linear Equations in Two Variables

Write an equation of a line given its slope and y-intercept.

If we know the slope of a line and its y-intercept, we can

write its equation by substituting these values into the

above equation.

Copyright © 2010 Pearson Education, Inc. All rights reserved. Sec 4.3 - 6

Write an equation of a line given its slope and y-intercept.

If we know the slope of a line and its y-intercept, we can

write its equation by substituting these values into the

above equation.

Copyright © 2010 Pearson Education, Inc. All rights reserved. Sec 4.3 - 6

7.
4.3 Linear Equations in Two Variables

Writing an Equation of a Line

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Writing an Equation of a Line

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8.
4.3 Linear Equations in Two Variables

Graph Lines Using Slope and y-Intercept

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Graph Lines Using Slope and y-Intercept

Copyright © 2010 Pearson Education, Inc. All rights reserved. Sec 4.3 - 8

9.
4.3 Linear Equations in Two Variables

Write an equation of a line, given its slope and a point on the line.

If we know the slope m of a line and the coordinates of a

point on the line, we can determine its equation.

Copyright © 2010 Pearson Education, Inc. All rights reserved. Sec 4.3 - 9

Write an equation of a line, given its slope and a point on the line.

If we know the slope m of a line and the coordinates of a

point on the line, we can determine its equation.

Copyright © 2010 Pearson Education, Inc. All rights reserved. Sec 4.3 - 9

10.
4.3 Linear Equations in Two Variables

Write an equation of a line, given its slope and a point on the line.

If we know the slope of a line and the coordinates of a

single point on the line, we can write the equation of the

line by substituting these values into the equation above.

Copyright © 2010 Pearson Education, Inc. All rights reserved. Sec 4.3 - 10

Write an equation of a line, given its slope and a point on the line.

If we know the slope of a line and the coordinates of a

single point on the line, we can write the equation of the

line by substituting these values into the equation above.

Copyright © 2010 Pearson Education, Inc. All rights reserved. Sec 4.3 - 10

11.
4.3 Linear Equations in Two Variables

Finding the Equation of a Line, Given the Slope and a Point

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Finding the Equation of a Line, Given the Slope and a Point

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12.
4.3 Linear Equations in Two Variables

Finding an Equation of a Line, Given Two Points

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Finding an Equation of a Line, Given Two Points

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13.
4.3 Linear Equations in Two Variables

Finding an Equation of a Line, Given Two Points

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Finding an Equation of a Line, Given Two Points

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14.
4.3 Linear Equations in Two Variables

Equations of Horizontal and Vertical Lines

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Equations of Horizontal and Vertical Lines

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15.
4.3 Linear Equations in Two Variables

Finding Equations of Parallel or Perpendicular Lines

Recall that parallel lines have the same slope and

perpendicular lines have slopes with product –1.

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Finding Equations of Parallel or Perpendicular Lines

Recall that parallel lines have the same slope and

perpendicular lines have slopes with product –1.

Copyright © 2010 Pearson Education, Inc. All rights reserved. Sec 4.3 - 15

16.
4.3 Linear Equations in Two Variables

Finding Equations of Parallel or Perpendicular Lines

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Finding Equations of Parallel or Perpendicular Lines

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17.
4.3 Linear Equations in Two Variables

Finding Equations of Parallel or Perpendicular Lines

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Finding Equations of Parallel or Perpendicular Lines

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18.
4.3 Linear Equations in Two Variables

Finding Equations of Parallel or Perpendicular Lines

6

–6 6

–6

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Finding Equations of Parallel or Perpendicular Lines

6

–6 6

–6

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19.
4.3 Linear Equations in Two Variables

Finding Equations of Parallel or Perpendicular Lines

Recall that parallel lines have the same slope and

perpendicular lines have slopes with product –1.

Copyright © 2010 Pearson Education, Inc. All rights reserved. Sec 4.3 - 19

Finding Equations of Parallel or Perpendicular Lines

Recall that parallel lines have the same slope and

perpendicular lines have slopes with product –1.

Copyright © 2010 Pearson Education, Inc. All rights reserved. Sec 4.3 - 19

20.
4.3 Linear Equations in Two Variables

Finding Equations of Parallel or Perpendicular Lines

Copyright © 2010 Pearson Education, Inc. All rights reserved. Sec 4.3 - 20

Finding Equations of Parallel or Perpendicular Lines

Copyright © 2010 Pearson Education, Inc. All rights reserved. Sec 4.3 - 20

21.
4.3 Linear Equations in Two Variables

Finding Equations of Parallel or Perpendicular Lines

Copyright © 2010 Pearson Education, Inc. All rights reserved. Sec 4.3 - 21

Finding Equations of Parallel or Perpendicular Lines

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22.
4.3 Linear Equations in Two Variables

Finding Equations of Parallel or Perpendicular Lines

6

–6 6

–6

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Finding Equations of Parallel or Perpendicular Lines

6

–6 6

–6

Copyright © 2010 Pearson Education, Inc. All rights reserved. Sec 4.3 - 22

23.
4.3 Linear Equations in Two Variables

Forms of Linear Equations

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Forms of Linear Equations

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24.
4.3 Linear Equations in Two Variables

Determining a Linear Equation to Describe Real Data

A veterinarian charges $45 to visit a farm where cattle are

raised. The price to vaccinate each animal is $18. Write

an equation that defines the total bill that the veterinarian

will submit to vaccinate all the cattle at the farm.

Copyright © 2010 Pearson Education, Inc. All rights reserved. Sec 4.3 - 24

Determining a Linear Equation to Describe Real Data

A veterinarian charges $45 to visit a farm where cattle are

raised. The price to vaccinate each animal is $18. Write

an equation that defines the total bill that the veterinarian

will submit to vaccinate all the cattle at the farm.

Copyright © 2010 Pearson Education, Inc. All rights reserved. Sec 4.3 - 24