Quadratic Week 2 Assignment

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

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

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

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

How many zeros does this parabola have? 

• 3
• 2
• 0
• 1

Mark the roots of the parabola.

What key feature tells the initial height of the roller coaster?

• y-intercept

• positive root/

  x-intercept

• x of vertex

• y of vertex

How high was the ball when it was initially (first) thrown? Choose the best answer.

• 0 feet because this is the y-intercept.

• 3 feet because this is the y-intercept.

• 4 seconds because this is the axis of symmetry.

• 5 feet because this is the y-value of the vertex (highest point).

A rocket is launched.

Which key feature tells us about the time it took for the rocket to get to the ground?

• positive

  x-intercept

• y-intercept

• x of vertex

• y of vertex

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