Real World Parabola Questions

Mr. Ernest's science class built and launched rockets. The graph below shows the height, in feet, over time, in seconds, of a student's rocket. Use the graph to answer the questions below. How long was the rocket in the air?

• 1 second

• 7 seconds

• 14 seconds

• 0 seconds

The graph below shows the height, in feet, over time, in seconds, of a student's rocket. Use the graph to answer the questions below. What was the maximum height the rocket reached?

• 25 feet

• 45 feet

• 65 feet

• 85 feet

The graph below shows the height, in feet, over time, in seconds, of a student's rocket. Use the graph to answer the questions below. How long did it take the rocket to reach its maximum height?

• 1 second

• 5 seconds

• 7 seconds

• 11 seconds

Adam graphs a quadratic function. The vertex of the parabola he graphs is located at (5, 0). Which of the following is the axis of symmetry

• x = -5

• x = 0

• x = 5

• x = y

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Over what interval is the function shown in the table decreasing? Use no spaces in your answer. Only use numbers and inequality signs.

Answer explanation

The parabola is opened upwards since a = 3. Although it is more narrow than the parent function, it is still decreasing on the interval

(-infinity, 0). Since we read from left to right, as we look at x values that are less than 0, as we get closer and closer to 0 the y values decrease. Therefore the interval x<0 is decreasing and x>0 is increasing.

The height of a basketball after it bounces is represented by h(t) = -8t² + 50t where h represents the height, in feet, and t represents the number of seconds that have passed since the ball bounced off the ground.

What represents the domain of this function?

• Height in feet

• Height in inches

• Number of seconds that have passed

• Number of basketballs

The LNHS Lions stadium seats about 2,000 people. The tickets sell for $6 each. The function f(x) = 6x represents the situation where x is the number of people in attendance and f(x) is the amount of money LNHS makes as revenue.

What is the range of the situation?

• 0 < f(x) < 6

• 0 < f(x) < 2,000

• 0 < f(x) < 12,000

• 2,000 < f(x) < 12,000