Area and Linear Models

Which of the following situations could be descried by the equation y=120-25x?

• There are 120 people in the football stadium, and 25 more are entering each hour.
• A plumber charges $25 for a house call and $120 per hour.
• A teacher has 120 students. Her third period has 25 students
• There are 120 gallons of water in a tank. It releases water at a rate of 25 gallons per minute

Which statement below accurately represents the graph?

• $100 is earned for each hour worked
• $100 is earned for every 2 hours worked
• $500 is earned for every 8 hours worked
• $400 is earned for every 6 hours worked

The equation below represents an elevator's height after an amount of seconds. Using this equation, what should the height of the elevator be after 14 seconds?

y = -3.8x + 290

• 80

• 236.8

• -80

• 72.6

The amount of water in the bucket ( in pints) can be modeled by the equation

y = 2x + 7 where n is the number of pitchers used to put water in the bucket.  If the bucket contains 29 pints of water, how many pitchers of water were used to fill it?

• 11

• 65

• 9

• 18

The commission of a sales representative can be modeled by C = 4n - 10, where n is the number of items sold, and C is the commission.  If the sales representative sales 30 items, how much commission will they earn?

• $20

• $120

• $5

• $110

The GPA of a student can be predicted using the equation GPA = 1.4h + 1.4  where h is the hours the student spends studying.  What is the expected GPA of a student that spends no hours studying?

• 2.4

• 1.4

• not enough information

• 2.8

R(n)=125 + 80n models the amount of money R(n) in the register after selling n tickets. How many tickets must be sold to have $18,445 in the register? 

• 233
• 92
• 229
• 119

A driving range charges $4 to rent a golf club plus $2.75 for every bucket of golf balls you hit. Write an equation that shows the total cost c of hitting b buckets of golf balls.

• c = 2.75b + 4
• c = 2.75b
• c =  4b- 2.75
• c = 2.75b - 4

The function defined by y = 12x + 500 represents the total amount given to charity (y) as a function of the number of students present at the event (x). If the school would like to donate $3000 to its favorite charity, how many students will have to attend to make that happen?

• 229

• 219

• 239

• 209