Quadratic Functions Solutions and Word Problems

A ball is thrown into the air with an upward velocity of 100 ft/s. Its height, h, after t seconds is given by the function
 h = -16t² + 64t + 960.
How many seconds did it take for the ball to reach its maximum height?

• 10 seconds

• 64 seconds

• 960 seconds

• 2 seconds

Your nephew is standing on his deck and tosses his toy up into the air. The equation h= -2t^2+5t+3 models the toy’s height h in feet from the ground at t seconds after he threw it. How high is the toy after 2 seconds?

• 1.25

• 3

• 4

• 5
  

• 6.13
  

A kid launches a rock off of a cliff. The height of the rock after t seconds can be modeled by the graph shown. What is the height of the cliff?

• 1.094 ft

• 174.141 ft

• 155 ft

• 4.393 ft

• None of the above

A kid launches a rock off of a cliff. The height of the rock after t seconds can be modeled by the graph shown. When does the rock hit the ground?

• 1.094 seconds

• 174.141 seconds

• 155 seconds

• 4.393 seconds

• None of the above

Your teacher gives you an equation in vertex form and wants you to convert it to standard form. Which one of the following describes the steps in the correct order?

• 1- Distribute the "a" value.

  2- Square the expression in parentheses.

  3- Combine like terms.

• 1- Square the expression in parentheses.

  2- Combine Like Terms.

  3- Distribute the "a" value.

• 1- Square the expression in parentheses.

  2- Distribute the "a" value.

  3- Combine like terms.

If each mark on the x-axis represents one second, when did the object reach the ground?

• 2.5 seconds

• 6 seconds

• 5.5 seconds

• 5 seconds

The height of a water balloon that is launched into the air is given by h(t) = -5t² + 40t + 2. From what height was the balloon released?

• 2 meters

• 5 meters

• 40 meters

• 20 meters

If a toy rocket is launched vertically upward from ground level with an initial velocity of 128 feet per second, then its height h after t seconds is given by the equation

h(t) = -16t² +128t

When will the object reach its maximum height?

• 4 ft

• 0 seconds

• 0 ft

• 4 seconds

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

A frog is sitting on the ground when he is scared by a big dog. His movement is modeled by the equation h = -6t² + 6t where h is the frog's height at any given time, t . How many seconds until the frog is back on the ground?

• 0.5 seconds

• 1 second

• 1.5 seconds

• 2 seconds

• 3 seconds