SOLUTION: can someone help me please solve this quadratic formula You are driving along the highway when suddenly a large box falls off of a truck in front of you and dumps metal parts a

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Question 769511: can someone help me please solve this quadratic formula
You are driving along the highway when suddenly a large box falls off of a truck in front of you and dumps metal parts all over the roadway. You hit the brakes and decelerate as fast as you can. The distance D in feet that your car travels before you stop is related to your initial speed S by an equation like D = S^2 / 9. Find the initial speed S that corresponds to a stopping distance of 200 feet.
Speed in mph (positive answer only, nearest integer):

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
+D+=+s%5E2+%2F+9+
+200+=+S%5E2+%2F+9+
+S%5E2+=+1800+
+S%5E2+=+900%2A2+
+S+=+30%2Asqrt%282%29+
+S+=+30%2A1.414+
+S+=+42.42+
The initial speed is 42 mi/hr