Graphing Proportional Relationships
Equations of Proportional Relationships
Identifying Proportional Relationships
Ratios & Rates
Proportions
100
What is the ordered pair for the origin?
** Don't forget your parentheses around the ordered pair! **
(0,0)
100
Is this equation proportional? y= 3x
If so, what is the constant of proportionality? (K)
Yes
k=3
100
How do you find the constant of proportionality?
Y/X
100
What operation do you use to find the unit rate?
Division
100
The ratio of cats to dogs in a pet store is 4:5. If there are 20 cats, how many dogs are there?
25 dogs
200
A relationship between two quantities that is changing at a CONSTANT rate is:
a. proportional
b. nonproportional
a. proportional
200
Is this equation proportional? If so what is the constant of proportionality? (K=)
y= 4x + 10
Not proportional
200
Is the graph a proportional relationship? Why?
NO
Does not go through the origin
200
Write the ratio of boys to girls in the class right now?
answer will very on the class
200
In a class, the ratio of boys to girls is 3:4. If there are 21 boys in the class, how many girls are there?
28 girls
300
What are the two rules to know if a graph is proportional?
1. The line is straight (to show a constant rate)
2. The line goes through the origin (0,0)
300
Is this equation proportional? If so what is the constant of proportionality? (K=)
y= ¾ x
proportional
k= 3/4
300
Is the table proportional?
No
300
A recipe calls for 4 cups of flour and 6 cups of sugar. What is the ratio of sugar to flour?
3/2
300
If 5 pizzas cost $60, how much will 9 pizzas cost?
108 dollars
400
Is this graph proportional? Explain WHY.
Yes, it is a straight line that goes through the origin.
400
Using this graph, What is the equation? Write your constant of proportionality as a FRACTION. 
y= 1/6x
400
Is the table proportional?
Yes it is proportional
400
If a car travels 120 miles in 2 hour, what is the rate in miles per hour?
60 mph
400
A smoothie recipe requires 3 bananas for every 6 cups of milk. If a chef wants to make a larger batch using 10 cups of milk, how many bananas will be needed?
5 bananas
500
A recipe for lemonade is given by the equation y = 4x where x represents the cups of lemonade mix and y represents the cups of water.
If Tyler had 16 cups of lemonade mix, how many cups of water would he need for each recipe?
64 cups of water
500
Write an equation for the table given the table is proportional.
y = 3/2 x
or y = 1 1/2x
or y = 1.5x
500
True or False:
The equation below represents a proportional relationship, EXPLAIN?
y = 7x - 2
False, it is not written in the form y=kx. The -2 makes this non-proportional
500
Seth's family plans to drive 220 miles to their vacation spot. They would like to complete the drive in 4 hours. Find the average speed in miles per hour needed to make the trip in the desired time.
55 mph
500
An artist is creating a mural that is 3 feet tall and 5 feet wide. If the artist wants to scale the mural up to be 9 feet tall, what will be the width of the mural to maintain the same proportions?
15 feet wide