1. 4.1 – Plot Points in a Coordinate Plane
Grade Distribution
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4.1 – Plot Points in a Coordinate Plane

2. Plot Points in a Coordinate Plane
Section 4.1
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4.1 – Plot Points in a Coordinate Plane

3. 4.1 – Plot Points in a Coordinate Plane
Definitions
X–coordinate is a point that lies left and right
Y–coordinate is a point that lies up and down
X–axis is horizontal axis
Y–axis is vertical axis
Independent Variable is on the x–axis
Dependent Variable is on the y–axis
Ordered pair is a pair with an x–coordinate and a y–coordinate (x, y)
Coordinate plane is a grid system to graph ordered pairs
Origin is where all the points start off at. (0, 0)
Scatterplots are horizontal and vertical axes to plot data points
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4.1 – Plot Points in a Coordinate Plane

4. 4.1 – Plot Points in a Coordinate Plane
What’s the point?
Determine the x and y–coordinate of this point
(2, 4)
X–coordinate
Y–coordinate
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4.1 – Plot Points in a Coordinate Plane

5. 4.1 – Plot Points in a Coordinate Plane
The plane truth
Y–axis
X–axis
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4.1 – Plot Points in a Coordinate Plane

6. 4.1 – Plot Points in a Coordinate Plane
Example 1
Plot (2, 4) into the coordinate plane
Point: (2, 4)
Start here
(0,0) origin
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4.1 – Plot Points in a Coordinate Plane

7. 4.1 – Plot Points in a Coordinate Plane
Your Turn
Identify the points of letters A, B, and plot (4, 7/4)
(1, 6) A
(2, 3.5) B
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4.1 – Plot Points in a Coordinate Plane

8. 4.1 – Plot Points in a Coordinate Plane
Consist of 4 different quadrants
Quadrant I: (+,+)
Quadrant II: (–,+)
Quadrant III: (–,–)
Quadrant IV: (+,–)
Graph goes counter clockwise
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4.1 – Plot Points in a Coordinate Plane

9. 4.1 – Plot Points in a Coordinate Plane
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4.1 – Plot Points in a Coordinate Plane

10. 4.1 – Plot Points in a Coordinate Plane
Example 2
Plot point (4, –2) and identify what quadrant it is located at.
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4.1 – Plot Points in a Coordinate Plane

11. 4.1 – Plot Points in a Coordinate Plane
Example 3
Plot point (0, –2) and identify what quadrant it is located at.
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4.1 – Plot Points in a Coordinate Plane

12. 4.1 – Plot Points in a Coordinate Plane
Your Turn
Plot point (–2, 0) and identify what quadrant it is located at.
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4.1 – Plot Points in a Coordinate Plane

13. Steps in Graphing a Function
Make a table by substituting the domain into the function
List the ordered pairs with parenthesis
Identify the range
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4.1 – Plot Points in a Coordinate Plane

14. 4.1 – Plot Points in a Coordinate Plane
Example 4
Graph the function y = 2x – 1 with the domain –2, –1, 0, 1, and 2 and identify the range of the function x
Process y –2
y = 2(–2) – 1 –5 –1
y = 2(–1) – 1 –3
y = 2(0) – 1 1
y = 2(1) – 1 2
y = 2(2) – 1 3 x
Process y –2
y = 2(–2) – 1 –1
y = 2(–1) – 1
y = 2(0) – 1 1
y = 2(1) – 1 2
y = 2(2) – 1 x
Process y –2 –1 1 2
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4.1 – Plot Points in a Coordinate Plane

15. 4.1 – Plot Points in a Coordinate Plane
Example 5
Graph the function y = –1/3x + 2 with the domain –6, –3, 0, 3, and 6 and identify the range of the function x
Process y –6 –3 1 2 3 6 4
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4.1 – Plot Points in a Coordinate Plane

16. 4.1 – Plot Points in a Coordinate Plane
Your Turn
Graph the function y = –1/2x + 1 with the domain –4, –2, 0, 2, and 4 and identify the range of the function x
Process y –4 3 –2 2 1 4 –1
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4.1 – Plot Points in a Coordinate Plane