Quadratics from Word Problems

The position of an object moving in a straight line is given by s = 2t² - 3t, where s is in meters and t is the time in seconds the object has been in motion. How long (to the nearest tenth) will it take the object to move 9 meters?

• 2.8 sec.

• 10.0 sec.

• 13.5 sec.

• 3.0 sec.

A ball is thrown downward from a window in a tall building. Its position at time t in seconds is s(t) = 16t² + 32t where s is in feet. How long (to the nearest tenth) will it take the ball to fall 224 feet?

• 2.7 sec.

• 8.4 sec.

• 3.7 sec.

• 2.9 sec.

If a toy rocket is launched from the ground and its height h after t seconds is given by the function h(t) = -8t² +64t.

When will the object reach its maximum height?

• 128 ft

• 0 seconds

• 0 ft

• 4 seconds

You are cliff diving with some friends. Your path to the water is modeled by h(t) = -16t^2 + 8t +24. How long will it take for you to hit the water? What are you solving for?

• roots

• axis of symmetry

• y-value of the vertex

• y-intercept

A ball is thrown into the air from the edge of a 48-foot-high cliff so that it eventually lands on the ground. The graph below shows the height, y, of the ball from the ground after x seconds.

For which interval is the ball's height always decreasing?

The sum of a number and its square is 72. Find the number(s).

• 8 or 9

• 8 or -9

• -8 or 9

• -8 or -9

Solve the word problem:  How fast would you reach the water if you jump of a cliff using the formula:    h(t) = -16t² + 8t + 24?

• 8

• 1

• 1.5

• 1/4

A model rocket is launched from the ground and it's path is modeled by the function h(t) = -16t² + 96t. What are you solving for?

• x-intercept

• y -intercept

• vertex

• axis of symmetry

A dolphin jumps from the water. The function h(t) = -16t² + 80t models the dolphin's height at any given time, t. What is the maximum height the dolphin jumps? What are you solving for?

• solutions

• y-intercept

• axis of symmetry

• y-value of the vertex

A ball is thrown into the air. Its height in feet after t seconds is given by the function h(t) = –5t² + 20t. How high will the ball be after 3 seconds?

• 20 ft

• 15 ft

• 5 ft

• 10 ft