Linear Relationships

If a line was drawn through the points, why would this line show a proportional relationship?

• It is not curved

• It is a vertical line

• It connects all the dots

• It goes through the origin

What can you use to represent linear relationships?

• verbal descriptions

• equations

• graphs

• tables

• all of the above

What is the rate of change for the following graph?

• 80

• 20

• 40

• 160

Clare owns a mobile pet grooming company. She charges $20 to come to your home plus $30 per hour to groom your pet. Which equation models the amount she charges over time?

A machine can make 14,400 screws in 8 hours. A second machine can make twice as many screws per hour. What is the constant of proportionality between the number of screws and the number of minutes for the second machine?

• 90 screws per minute

• 180 screws per minute

• 60 screws per minute

• 3,600 screws per minute

Jacob’s parents have allowed him to get a cell phone but he must pay his own cell phone bill. He pays a flat rate of $35 a month and 50¢ for every minute he talks on the phone. If c represents the total cost of the bill and m represents minutes talking on the phone, which equation best fits the situation?

• c = 5m + 35

• c = 3.5m + 50

• c = 0.5m + 35

• c = 35 + 100 + 0.5

A student spends the same amount each week for bus fare. In 5 weeks, he spends $115. Which equation shows this relationship? Let x = number of weeks.

• y = 3.22x

• y = 5x

• y = 23x

• y = 115x

What is the constant of proportionality for the relationship on the graph?

• 3.5

• 7

• 8

• 28

An electrician charges $25 to make a house call, plus $40 for every hour of work. Which equation shows how to find C, the total cost for having the electrician work for h hours?

• C = 25 + 40h

• C = 65 + h

• C= 65h

• C = 25h + 40

Which equation matches the graph?

• y = 1/3x + 3

• y = 3x

• y = x +3

• y = 3x + 3