Real World Quadratic Problems

Your younger sibling is standing on his deck, which is 4 feet off the ground. They toss their toy up into the air. The toy's height, h, from the ground at t seconds after they threw it is modeled by the function h(t) = -2t² + 7t + 4. How long does it take the toy to hit the ground? Hint: Use factor by grouping!!!

• .5 sec

• 2 sec

• 4 sec

• 8 sec

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.
When did the ball hit the ground?

• 10 seconds

• 2 seconds

• 5 seconds

• 7 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. The following functions reprsents the divers height (in feet) where t is time in seconds: h(t) = −16 t² + 8t + 24

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

• 22 meters

• 1.89 seconds

• 2 seconds

• 2 meters

• 18 meters

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

What algebraic term are you solving for if the word problem is: The equation for leaping off a cliff is
h(t) = -16t² + 8t +24.  How long will it take for you to hit the water?

• Roots (Solutions)

• Axis of Symmetry

• Vertex

• y-intercept

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