SOLUTION: Benjamin threw a rock straight up from a cliff that was
24ft above the water. If the height of the rock h, in feet, after t seconds is given by the equation h equals negati
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24ft above the water. If the height of the rock h, in feet, after t seconds is given by the equation h equals negati
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Question 1133275: Benjamin threw a rock straight up from a cliff that was
24ft above the water. If the height of the rock h, in feet, after t seconds is given by the equation h equals negative 16 t squared plus 20 t plus 2 h=−16t2+20t+24, how long will it take for the rock to hit the water? Answer by Boreal(15235) (Show Source):
You can put this solution on YOUR website! The equation's "24" is the height above the water. Solve this for h=0, water level
-16t^2+20t+24=0
-4t^2+5t+6=0 or 4t^2-5t-6=0
(4t+3)(t-2)=0
t=2 only positive root.
2 seconds ANSWER