SOLUTION: Robert threw a rock off a bridge into the river. The distance from the rock to the river is molded by the equation h=-16t^2-16t+60, where h is the height in ft. and t is the time i

Question 1154978: Robert threw a rock off a bridge into the river. The distance from the rock to the river is molded by the equation h=-16t^2-16t+60, where h is the height in ft. and t is the time in seconds. find out how long it took the rock to hit the surface. solve the equation by factoring.
Answer by MathLover1(20849) (Show Source): You can put this solution on YOUR website!
, where is the height in and is the time in seconds
the rock will hit the surface when
to find how long it will took the rock will hit the surface,plug in and solve for
........factor out
...write as

solutions:

if =>=>=>
if =>=>=> disregard negative solution

so, it took seconds the rock to hit the surface

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