aim: how do we graph equations of the form y = c and x = c
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Aim: How do we graph equations of the form y = c and x = c. Do Now: SAT Question How much is twice a number increased by 5, if half of the same number decreased by 5 is one?. x = number. y. 9. 8. 7. 6. x = -2. 5. - PowerPoint PPT PresentationTRANSCRIPT
Aim: Graphing Constants Course: Applied Geo.
Do Now: SAT QuestionHow much is twice a number increased by
5, if half of the same number decreased by 5 is one?
Aim: How do we graph equations of the form y = c and x = c
x = number
152
1x
62
1x
12x
?52 x
?5)12(2
29524
Aim: Graphing Constants Course: Applied Geo.
The x-coordinate is the same
Graph each of the following set of points: (-2,7), (-2, 5), (-2, 0), (-2, -3), (-2, -6)
x
y
1 2 3 4 5 6 7 8 9-1-2-3-4-5-6
1
2
3
4
5
6
7
8
9
-1
-2
-3
-4
-5
-6
-7
-8
-9
Name 3 other points that could be in this set.
Describe the relationship
Write a rule.
Identify the line as horizontal or vertical.
vertical
All x values are -2, and the line formed is parallel to the y axis
x = -2
x =
-2 (-2, 4), (-2, 1), (-2, -1)
Aim: Graphing Constants Course: Applied Geo.
x
y
1 2 3 4 5 6 7 8 9-1-2-3-4-5-6
1
2
3
4
5
6
7
8
9
-1
-2
-3
-4
-5
-6
-7
-8
-9
The y-coordinate is the same
Graph each of the following set of points: (-4, -4), (-2, -4), (0, -4), (2, -4), (7, -4)
Name 3 other points that could be in this set.
Describe the relationship
Write a rule.
Identify the line as horizontal or vertical.
horizontal
All y values are -4, and the line formed is parallel to the x axis
(-6, -4), (4, -4), (9, -4)
y = -4
y = -4
Aim: Graphing Constants Course: Applied Geo.
Graphs/Equations of Horizontal & Vertical Lines
Graphing a line parallel to an axis.
x = c & y = c
x = c y = c
An equation of a line parallel to the y-axis with x-intercept c is
x = c
An equation of a line parallel to the x-axis with y-intercept c is
y = c
Intercept - the point where a line crosses an axis
0, 4
y = 4
3, 0x =
3
Aim: Graphing Constants Course: Applied Geo.
Model Problem
Draw the graph of
1. y = -5 2. x = 2 3. y = 3
y = -5x
= 2
y = 3
Write an equation for the line that is parallel to the x-axis and whose y-intercept is -3
y = -3
Write an equation for the line that is parallel to the y-axis and whose x-intercept is 2½ x = 2½
Aim: Graphing Constants Course: Applied Geo.
Model Problems
6
4
2
-2
-4
-6
-5 5
Write the algebraic expression for each line.
Aim: Graphing Constants Course: Applied Geo.
Model Problem
What is the equation for a line passing through (6, 4) and parallel to the line passing through (4, 2) and (6, 2)?
6
4
2
-2
-4
-6
-5 5
(6, 4)
(4, 2) (6, 2)y = 2
y = 4
What is the equation for the x-axis? y = 0
What is the equation for the y-axis? x = 0