Several teachers left their school and drove separately on the same road to attend training. The graph shows the distance traveled by each teacher after three hours of nonstop driving at four different speeds.

Which teacher drove at the slowest rate to the training?

A. Mrs. Lozano
Incorrect. This line is the steepest, so the rate is the fastest.

B. Mrs. Coe
Incorrect. This line is too steep, the rate is faster than 2 other teachers.

C. Mr. Castanon
Incorrect. This line is too steep, the rate is faster than 2 other teachers.

D. Mr. Poole
Correct! Since this line is the least steep, it represents the slowest rate.

What are the slope and y-intercept of a line that contains the point (–1, 3) and has the same y-intercept as 1 2x + 5 ?

A. m = 1 2
     b = 5
Incorrect. This line would not pass through point (-1, 3).

B. m = 1 2
     b = 3

Incorrect. This line would not pass through point (-1, 3).

C. m = 2
     b = 5
Correct! This line would pass through point (-1, 3) and has the same y-intercept as y = 1 2x + 5.

D. m = 2
     b = 3
Incorrect. This has the correct slope, but the line would not pass through point (-1, 3).

The line segment on the graph shows the amount of water in a swimming pool over a period of time. Which of the following best describes the slope of the line segment?

A. Water evaporates at a rate of about 10 gallons per day.
Incorrect. It takes 2.5 days for the water level to drop 10 gallon.

B. Water evaporates at a rate of about 4 gallons per day.
Correct! Since the water level drops 10 gallons over a period of 2.5 days.

C. Water evaporates at a rate of about 2 gallons per day.
Incorrect. You are reading the labels on the axis incorrectly.

D. Water evaporates at a rate of about 1 gallon per day.
Incorrect. The water is evaporating at a rate of 4 gallons per day.

A local delivery services has posted the cost of delivering packages in the table shown below.

Which of the following best describes the meaning of the slope of the line representing this situation?

A. The cost of delivering a package is $2 per ounce.
Incorrect. The change in cost divided by the change in weight is 0.2.

B. The cost of delivering a package is $0.20 per ounce.
Correct! The change in cost divided by the change in weight is 0.2.

C. The cost of delivering a package is $0.50 per ounce.
Incorrect. The change in cost divided by the change in weight is 0.2.

D. The cost of delivering a package is $0.60 per ounce.
Incorrect. The change in cost divided by the change in weight is 0.2.