Quadratics Initial Height

What is the initial (starting) height of an object following this path?  h(t) = -16t² +20t + 6

• -16 feet 

• 0 feet

• 20 feet 

• 6 feet 

If path of a projectile is modeled by: 
h(t) = -16t² + 20t +6, what is the height after 1 second? 

• 6 feet 

• 20 feet 

• 10 feet 

• 4 feet 

Which equation has a vertex of (-3, 4)?

• y = 2(x+3)² + 4

• y = (x+3)² - 4

• y = (x-3)² + 4

• y = 2(x - 3)² + 4

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

• 2 meters

• 4 meters

• 5 meters

• 8 meters

A diver is standing on a platform above the pool. He jumps from the platform with an initial upward velocity of 8 ft/s. Use the formula h (t) = −16 t² + 8t + 24, where h is his height,in feet, above the water, t is the time, in seconds . How high is the platform?

• .25 ft

• 24 ft

• 25 ft

• 8 ft

• None of the above

What is the initial (starting) height of an object following this path? h(t) = -16t² +20t + 6

• -16 feet

• 0 feet

• 20 feet

• 6 feet

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.

Joe Mauer hits a fly ball.  You can track the height of the ball using the equation:   h(t) = -16t² + 140t + 2  
What was the starting
                        height of the ball?                                                                                      

• -16 feet

• 140 feet

• 2 feet

• 0 feet

Your friend passes you the ball during a soccer game. The height off the ground is modeled by the equation

h = -4t² + 12t. How high did the soccer ball get?

• 1.5

• 3

• 5

• 9

• 15

If I want to see the initial height of an object, I should _____________.

• Substitute x = 0 into the equation and evaluate.

• Use x = (-b /2a) as my answer.

• Find the y-coordinate of the vertex. 

• Set my equation = 0 and solve.