A rollercoaster ride reaches a height of 100 feet before it sharply drops. The height above the ground of the rollercoaster car during the drop is modeled by the function, h(t)=10t^2−60t+100 , where t is measured in seconds since the car started its decline.

The model is accurate for 0≤t≤50≤t≤5 .

On this portion of the ride, how long does the car take to reach a minimum height from the ground before rising again?

2.25 s

3 s

3.5 s

4.25 s

kikidylm Feb 20, 2019