SOLUTION: Please keep in mind that this equation is set up like v squared, and the 0 is below the 2. It almost looks like 2/0 but there is not fraction line. I just couldn't type it like tha

Algebra ->  Customizable Word Problem Solvers  -> Travel -> SOLUTION: Please keep in mind that this equation is set up like v squared, and the 0 is below the 2. It almost looks like 2/0 but there is not fraction line. I just couldn't type it like tha      Log On

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Question 1129037: Please keep in mind that this equation is set up like v squared, and the 0 is below the 2. It almost looks like 2/0 but there is not fraction line. I just couldn't type it like that. Please feel free to email me for a picture.

The formula for braking distance of a car:
d=0.018268 * v^2/0
where v0 is the initial velocity of the car (feet per second) and d is the braking distance (ft). In this model, the roadway grade is kept constant at 5% and the coefficient of friction at 0.8. In a school zone, you want the maximum breaking distance to be 10 feet since this seems like a reasonable distance to see a child who might be in the way of a driver.
A)What should you set as the speed limit (i.e. initial velocity of the car) so that the breaking distance is 10 feet or less? Round the the nearest foot per second.
_____ feet per second.

b. The equation x^2=9 has two solutions: 3 and -3. With that in mind, what is the other solution to the equation 10=0.018268⋅v^20, besides what you answered in (a)? Why is this other solution not the correct answer to the question in (a)?
The second solution is _____ feet per second.
It is not an answer to the question in part a because:
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!

A)
What should you set as the speed limit (i.e. initial velocity of the car) so that the breaking distance is 10 feet or less? Round the the nearest foot per second.
_____ feet per second.

d=0.018268+%2A+v%5B0%5D%5E2
if
d+=+10ft
10=0.018268+%2A+v%5B0%5D%5E2
v%5B0%5D%5E2=10%2F0.018268
v%5B0%5D%5E2=547.40529888
v%5B0%5D=sqrt%28547.40529888%29
v%5B0%5D=23%28ft%2Fs%29

b.The equation x^2=9 has two solutions: 3 and -3. With that in mind, what is the other solution to the equation 10=0.018268⋅v^20, besides what you answered in (a)? Why is this other solution not the correct answer to the question in (a)?
The second solution is _____ feet per second.


v%5B0%5D=+-23%28ft%2Fs%29
The second solution is __-23%28ft%2Fs%29___ feet per second.
Why is this other solution not the correct answer to the question in (a)?
It is not an answer to the question in part a because: velocity cannot be negative