Quadratic Problems

The function f(t) = -5t²+20t + 60 models the approximate height of an object t seconds after it is launched. How many seconds does it take the object to hit the ground? 

• 4 seconds

• -2 seconds

• -6 seconds

• 6 seconds

Members of the math club launch a model rocket from ground level with an initial velocity of 96 ft/sec. This can be modeled with the function h(t) = -16t² + 96t. When does the rocket hit the ground?

• 7 seconds

• 6 seconds

• 3 seconds

• 8 seconds

A diver is standing on a platform above the pool. He jumps form 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 above the water, t is the time, v is his starting upward velocity, and s is his starting height. How high is the platform?

• .25 ft

• 24 ft

• 25 ft

• 8 ft

• 95 feet

• 45 feet

• 70 feet

• 171.56 feet

• 70 feet

• 95 feet

• 149 feet

• -16 feet

• 10 seconds

• 64 seconds

• 960 seconds

• 2 seconds

Jason jumped off of a cliff into the ocean in Acapulco while vacationing with some friends. His height as a function of time could be modeled by the function h(t) = –16t² + 16t + 480, where t is the time in seconds and h is the height in feet. How long does it take Jason to hit the water?

• -16 seconds

• -6 seconds

• 0 seconds

• 6 seconds

Your nephew is standing on his deck, which is 4 feet off the ground. He tosses his toy up into the air. The equation

h = -2t² + 7t + 4 models the toy's height, h, from the ground at t seconds after he threw it. How high is the toy after 1 second?

• 2

• 4

• 9

• 10

• 15

How many zeros does this parabola have? 

• 3

• 2

• 0

• 1

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