Interpreting Function Relationships

Sandra has a $20 itunes gift card and spends $3 each month.  Which equation can be used to find how much money Sandra has on her giftcard after x months?

• y = 3x + 20

• y = 3 + 20x

• y = -3x + 20

• y = -20x + 3

Which equation shows the number of bottles left after x days?
A family buys a case of water with 48 bottles and drinks 5 bottles per day.

• y = 48x + 5

• y = -5 + 48x

• y = -5x - 48

• y = 48 - 5x

Dorothy loves to make cakes.  The following table shows how the number of eggs that she has left changes as she makes cakes.
What is the meaning of the y-intercept?

• She uses 5 eggs for every 2 cakes.

• She started with 47 eggs.

• She uses 47 eggs for every 0 cakes.

• She started with 5 eggs.

What is the meaning of the y-intercept?

• The weight in the bucket increases by 1 pound per pound of sand.

• Before sand is put in the bucket, it weighs 1 pound.

• The starting weight of the sand is 1 pound.

• The weight in the bucket decreases by 1 pound per pound of sand.

What type of association does this graph have?

• positive

• negative

• none

• all of the above

The scatter plot shows the relationship between the number of chapters and the total number of pages for several books.  Use the trend line to predict how many chapters would be in a book with 180 pages. 

• 12 chapters

• 15 chapters

• 18 chapters

• 21 chapters

The equation of the trend line
is  y= 1/2x +1. What does the x variable represent? 

• The number of laps

• The amount of time in hours

• The amount of time in minutes

• How long it takes to go 0 laps

What is the equation for the line of best fit in the graph pictured?

• y = 5/3x + 375

• y = 1/3x + 475

• y = 5/3x + 3

• y = 1/3x + 375

The equation of the trend line
is  y= 1/2x +1
How many laps can a bicycle
make around the park in
23 minutes?    

• 44 laps

• 12 1/2 laps

• 23 laps

The equation y=10x represents the amount of allowance, y, in dollars, that Jacob receives for doing x hours of chores. Which statement interprets the slope of this equation?

• Jacob does chores for $0 per hour.

• Jacob does chores for $10 per hour.

• Jacob receives $0 of allowance money before doing any chores.

• Jacob receives $10 of allowance money before doing any chores.