Quadratic Applications Algebra

Alain throws a stone off a bridge into a river below. The stone's height (in meters above the water), x seconds after Alain threw it, is modeled by:
h(x)= -5x² + 10x + 15
What is the maximum height of the stone?

• 15 meters

• 16.5 meters

• 20 meters

• 22.2 meters

An object in launched directly upward at 64 feet per second (ft/s) from a platform 80 feet high. Its height is represented by the equation s(t) = –16t² + 64t + 80. What will be the object's maximum height? 

• 2 ft

• 80 ft

• 144 ft

• 64 ft

A soccer ball is kicked from the ground with an initial upward velocity of 90 feet per second. The equation h=-16t² + 90t gives the height h of the ball after t seconds.
How many seconds will it take the ball to hit the ground?

• 126.56 ft

• 5.625 sec

• 2.81 sec

• 0 ft

Rafael drops a ball from a third-story window. This equation represents the approximate height, h, in meters, of the ball above the ground after it falls for t seconds.
h = -5t² + 45 
When is the ball at ground level?

• only at t = 0 seconds 

• only at t = 3 seconds

• only at t = 9 seconds

• at both t = 0 seconds and t = 3 seconds

Alain throws a stone off a bridge into a river below. The stone's height (in meters above the water), x seconds after Alain threw it, is modeled by:
h(x)= -5x² + 10x + 15
How long does it take the stone to reach its highest point?

• 1 seconds

• 1.5 seconds

• 2 seconds

• 3 seconds

You are trying to dunk a basketball. You need to jump 2.5 feet in the air to dunk the ball. The height that your feet are above the ground is given by the function:
h(t) = -16t² + 12t
Will you be able to dunk the basketball?

• Yes

• No

• As long as I'm wearing Air Jordans

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

• 9 seconds

A diver is standing on a platform above the pool. He jumps form the platform with an initi8al 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

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

• 9 seconds

The profit from selling local ballet tickets depends on the ticket price.  Using past receipts, we find that the profit can be modeled by the function p= -15x² +600x +60 , where x is the price of each ticket.  What is the maximum profit you can make from selling tickets?

• $6060

• $20

• $600

• $10,250