Question 770359
Investigators at a traffic accident use the equation: D = 0.04v2 + 0.8v where v is the velocity (speed in mph) of the car before starting to stop and D is the stopping distance (length of the skid marks). If the skid marks are 192 feet long, how fast was the car traveling prior to the accident?
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Solve:
0.04v^2+0.8v-192 = 0
4v^2 + 80v - 19200 = 0
v^2  +20v - 4800 = 0
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(v-60)(V+80) = o
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v = 60 mph
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Cheers,
Stan H.
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