Question 955517
A small rock sits on the edge of a tall building. A strong wind blows the rock off the edge. The distance, in feet, between the rock and the ground tseconds after the rock leaves the edge is given by d= -16t^2 - 4t + 472.

How many seconds after the rock leaves the edge is it 460 feet from the ground?
-16t^2 - 4t + 472 = 460
Solve for t.
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How many seconds after the rock leaves the edge does it hit the ground?
-16t^2 - 4t + 472 = 0
Solve for t.