# Linear Equations in Two Variables

Contributed by:
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.
Sec 4.3 - 1
2. Chapter 4
Graphs, Linear Equations,
and Functions
Sec 4.3 - 2
3. 4.3
Linear Equations in Two
Variables
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.
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.
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.
7. 4.3 Linear Equations in Two Variables
Writing an Equation of a Line
8. 4.3 Linear Equations in Two Variables
Graph Lines Using Slope and y-Intercept
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.
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.
11. 4.3 Linear Equations in Two Variables
Finding the Equation of a Line, Given the Slope and a Point
12. 4.3 Linear Equations in Two Variables
Finding an Equation of a Line, Given Two Points
13. 4.3 Linear Equations in Two Variables
Finding an Equation of a Line, Given Two Points
14. 4.3 Linear Equations in Two Variables
Equations of Horizontal and Vertical Lines
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.
16. 4.3 Linear Equations in Two Variables
Finding Equations of Parallel or Perpendicular Lines
17. 4.3 Linear Equations in Two Variables
Finding Equations of Parallel or Perpendicular Lines
18. 4.3 Linear Equations in Two Variables
Finding Equations of Parallel or Perpendicular Lines
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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.
20. 4.3 Linear Equations in Two Variables
Finding Equations of Parallel or Perpendicular Lines
21. 4.3 Linear Equations in Two Variables
Finding Equations of Parallel or Perpendicular Lines
22. 4.3 Linear Equations in Two Variables
Finding Equations of Parallel or Perpendicular Lines
6
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