Applications of Quadratic Functions

A rock is dropped from a bridge 320 ft. above a river. The pathway that the rock takes can be modeled by the equation h = -16t² + 320. How long will it take for the rock to reach the river (i.e. hit the "ground")?

• 2.5 sec

• 3.5 sec

• 4.5 sec

• 3.8 sec

April shoots an arrow upward at a speed of 80 ft/sec from a platform of 25 ft. high. The pathway of the arrow can be represented by the equation h = -16t² + 80t + 25, where h is the height and t is the time in seconds. What is the maximum height that the arrow reaches?

• 80 ft.

• 90 ft.

• 140 ft.

• 125 ft.

A toy rocket is launched and its height is modeled by the equation h = -16t² + 32t + 48. What is the initial heigh of the object?

• 48 ft.

• 16 ft.

• 32 ft.

• 2 ft.

h(t) = -16t² + 20t +6, what is the height after 1 second?

• 6 feet 

• 20 feet 

• 10 feet 

• 4 feet 

Which of the following is true about the graph of this equation? Select all that apply.

• y-intercept is at (0,3)

• y-intercept is at (0,6)

• parabola opens up

• parabola opens down

Which of the following is true about the graph of this equation? Select all that apply.

• y-intercept is at (0,3)

• y-intercept is at (0,6)

• parabola opens up

• parabola opens down

A ball is thrown vertically into the air. Its height in feet after t seconds is given by the equation h(t) = –5t² + 20t. How many feet into the air will the ball be at 3 seconds?

Mathematical Equivalence

OFF

Which answer choice describes  y = -3x² +7x - 2 accurately?

• opens up with a maximum

• opens up with a minimum

• opens down with a maximum

• opens down with a minimum 

An object in launched directly upward and the height of the object is represented by the equation s(t) = –16t² + 64t + 80. What is the initial velocity the object is launched at?

• 64 feet

• 80 feet

• 16 feet

• -16 feet

A dolphin jumps from the water at at initial velocity of 16 feet per second. The equation h = -8t² + 16t models the dolphin's height at any given time, t. What is the maximum height the dolphin jumps?

• 1 foot

• 5 feet

• 7 feet

• 8 feet

• 12 feet