After an accident, police can estimate the speed that a car was traveling by measuring its skid marks. The formula r=2√5L can be used, where r is the speed, in miles per hour, and L is the length of the skid marks, in feet. Estimate the speed of a car that left skid marks (a) 50 ft long; (b) 180 ft long. How fast was the car traveling if it left skid marks 50 ft long? (Simplify your answer. Type an integer or a decimal. Round to the nearest tenth.) How fast was the car traveling if it left skid marks 160 ft long?
\(r=2\sqrt{5L}\) Is this correct?
I believe that is the formula for the problem.
This problem is easy, you have: \((a)L=50\\ (b)L=180\) Just plug and chug! :)
what is the problem use the formula
take care i think L should be convered in miles
@Addu5221 it says that L is in feet right in the problem.........
r=2√5 * 160 ?
then u apply the formula. where do u encounter the problem?
Not sure how to type the expression out to find the answer
51.2 mph?
For problem a we have that the length(L) of the skid marks is 50 feet. \(r=2\sqrt{5\times50}=2\sqrt{250}=2\times15.8114=31.6228~\text{mph}\)
31.6 = rounded to nearest tenth?
Correct. Now you try the next one!
I am confused with your answer, is it based off of 160 ft skid ?
That was for 50 right?
That was for the 50 foot skid. Now for the 180 foot skid :P
its 160 not 180
Well, then plug in 160.
I am having issues using the equation attachment
Just type it out like this 2*sqrt(###)
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