Interpret Equations

Kareena is saving money each week.  Her savings are represented by the equation y = 17.5x + 36, where y is the total amount of money she has saved up after x weeks.  

How much money, in dollars and cents, did she start with?

A cab company charges a pick-up fee as well as a charge for every mile traveled.  The equation y = 1.5x + 5 represents the total charge, y, when traveling x miles.  

What does the 1.5 mean in this situation?

• the distance driven, in miles, per dollar

• the cost, in dollars, per mile driven

• the flat pick-up fee

• the amount, in dollars, passengers are expected to tip

A cab company charges a pick-up fee as well as a charge for every mile traveled. 

The equation y = 1.5x + 5 represents the total charge, y, when traveling x miles.  

What does the 5 mean in this situation?

• the distance driven, in miles, per dollar

• the cost, in dollars, per mile driven

• the flat pick-up fee

• the amount, in dollars, passengers are expected to tip

Serenity is moving and must rent a truck.  There is an initial charge for the rental plus a fee per mile driven.  The total cost of renting the truck can be modeled by the equation C = 50 + 2.75m, where m is the number of miles driven. 

What is the initial fee to rent the truck, in dollars and cents?

Serenity is moving and must rent a truck.  There is an initial charge for the rental plus a fee per mile driven.  The total cost of renting the truck can be modeled by the equation C = 50 + 2.75m, where m is the number of miles driven.  What is the meaning of the 2.75?

• the initial rental fee

• the cost, in dollars, per mile driven

• the distance driven, in miles

• the cost, in dollars, per hour the truck is rented

Aubrey bought a plant and planted it in a pot near a window in his house.  As the plant grows, its height, in inches, can be modeled by the equation h = 5t + 12, where t is the number of months since Aubrey bought the plant. What does the 12 mean in this situation?

• the initial height of the plant, in inches

• how many months he has had the plant

• the amount, in inches, the plant grows each month

• the number of plants Aubrey purchased

Aubrey bought a plant and planted it in a pot near a window in his house.  As the plant grows, its height, in inches, can be modeled by the equation h = 5t + 12, where t is the number of months since Aubrey bought the plant. What does the 5 mean in this situation?

• the initial height of the plant, in inches

• how many months he has had the plant

• the amount, in inches, the plant grows each month

• the number of plants Aubrey purchased

The equation y = 3.5x + 10 represents the total cost, y, of buying x pounds of apples at a market.

What does the 3.5 mean in this situation?

• the cost, in dollars, per pound of apples

• the total cost of apples

• the number of pounds of apples bought

• the initial cost of buying apples

The equation y = 8x + 20 models the total number of pages, y, that Sarah can read in x hours.

What does the 8 mean in this situation?

• the total number of pages Sarah can read

• the number of pages Sarah reads per hour

• the number of hours Sarah reads

• the initial number of pages read

The equation y = 15x + 100 represents the total cost, y, of producing x units of a product in a factory.

What does the 100 mean in this situation?

• the cost, in dollars, per unit produced

• the total cost of production

• the fixed cost of production

• the number of units produced