Graphing Proportional Relationships
Equations of Proportional Relationships
Identifying Proportional Relationships
Proportional Relationships
Interpreting Proportional Graphs
100
What is the ordered pair of the origin?
(0,0)
100
In the equation y = 3x, what is the constant of proportionality?
3
100
True or False?
To find the constant of proportionality, you divide “x” by “y.”
FALSE
100
In an ordered pair (x, y) that represents the unit rate, which coordinate is 1?
x
100
Mr. Brooks is selling shirts for a fundraiser. He is plotting points on a graph to show his students how much he makes, in $. What would the point (0,0) mean in this situation.
If he sells 0 shirts, he will make $0.
200
Does this graph represent a proportional relationship? 
Yes
200
What are the characteristics of a proportional equation?
in the form of y=kx and nothing added or subtracted to it.
200
Does this graph show a proportional relationship? How do you know?
NO
Does not start at the origin
200
If the point (4, 3) is on the graph of a proportional relationship, what is the constant of proportionality?
3/4
200
Mr. Brooks is selling shirts for a fundraiser. He is plotting points on a graph to show his students how much he makes, in $. What would the point (1,8) mean in this situation.
Each shirt costs $8.
300
What two characteristics make a graph proportional?
Straight line
Starts at the origin (0,0)
300
Will the graph of the equation y = 3x + 5 be a straight line that starts at the origin?
no
300
(5,10) is a point on a line that represents a proportional relationship. What is the constant of proportionality?
2
300
What is the rate of apples to trees?
13 apples per tree
300
Mr. Brooks is selling shirts for a fundraiser. He is plotting points on a graph to show his students how much he makes, in $. What would the point (18,144) mean in this situation.
It means that when Mr. Brooks sells 18 shirts, he will make $144.
400
What is the constant of proportionality?
k=50
400
Is this equation proportional? y= (¾)x
yes
400
Does the table show a proportional relationship? If so, what is the constant of proportionality?
Yes; k=9
400
When creating this game, Mrs. Packer was able to create 3 questions every 5 minutes. How long would it take to create a game with 24 questions?
40 minutes
400
Mr. Brooks is selling shirts for a fundraiser. He is plotting points on a graph to show his students how much he makes, in $. The equation for this situation is y=8x. Would the point (8, 62) be on this graph?
No. The point would be (8, 64).
500
Is person A or person B walking faster?
person B - this person walks more miles in the same amount of hours.
500
If the constant of proportionality is 0.25, what is the equation for this relationship?
y = 0.25x
500
How do you know if a table is proportional?
When you divide the y value with its x value, you get the same constant of proportionality in each row.
500
A recipe for chocolate chip muffins needs 4 cups of flour to 1 cup of chocolate chips. Which of the following shows another correct ratio for the recipe?
a. 1 cup of flour for 1 cup of chocolate chips
b. 3 cups of flour to 1 cup of chocolate chips
c. 8 cups of flour to 2 cups of chocolate chips
c
500
Mr. Brooks is selling shirts for a fundraiser. He is plotting points on a graph to show his students how much he makes, in $. The equation for this situation is y=8x. Would the point (73, 584) be on this graph?
Yes. When Mr. Brooks sells 73 shirts, he will make $584.
600
Which of the following is proportional?
a. 
A
600
Kim tries to bike 15 miles (y) every 3 days (x).
What is the equation for this relationship?
y = 5x
600
Does the table show a proportional relationship between number of buses and number of students?
No
600
The point (4, 9) is on the graph of a proportional relationship. What is the equation for this graph?
y = (9/4)x
600
For 600 points, who is your favorite teacher at Avon Middle School South?
Mr. Brooks