Unit 1: Quiz 9 - Rate of Change

The graph shows the distance a ball has traveled x seconds after it was thrown. What is the average speed between 2 seconds and 8 seconds. intersects 2 seconds: (2, 3) intersects 8 seconds: (8, 6)

0.5 meters per second

If y varies directly as x, and y is 400 when x is r and y is r when x is 4, what is the numeric constant of variation in this relation?

10

If y varies directly as x, and y is 6 when x is 72, what is the value of y when x is 8?

2/3

T(d) is a function that relates the number of tickets sold for a movie to the number of days since the movie was released. The average rate of change in T(d) for the interval d = 4 and d = 10 is 0. Which statement must be true?

The same number of tickets was sold on the fourth day and tenth day.

Maria created a graph of B(t), the temperature over time. For the interval between t = 3 and t = 7, the average rate of change in her graph of B(t) is 8. Which statement must be true?

The temperature was 32 degrees higher when t = 7 than when t = 3.

Calculate the average rate of change of a function over a specified interval. Which expression can be used to determine the average rate of change in f(x) over the interval [2, 9]?

f(9) - f(2) / 9-2

The average rate of change of g(x) between x = 4 and x = 7 is 5/6. Which statement must be true?

g(7)-g(4) / 7-4 = 5/6

The height, h, of a falling object t seconds after it is dropped from a platform 300 feet above the ground is modeled by the function h(t) = 300-16t². Which expression could be used to determine the average rate at which the object falls during the first 3 seconds of its fall?

h(3)-h(0) / 3

If y varies directly as x, and y is 48 when x is 6, which expression can be used to find the value of y when x is 2?

y = 48/6 (2)

Which relation is a direct variation that contains the ordered pair (2, 7)?

y = 7/2 x