Question

Police can estimate the speed of a vehicle before the brakes are applied using the formula 0.75d=(s^2)/(30.25) where s is the speed in miles per hour and d is the length of the vehicle’s skid marks. What was the approximate speed of a vehicle that left a skid mark measuring 150 feet

Answer 1

150ft is 0.028 miles
So
(0.75x0.028)=(sxs) / 30.25
Meaning
(0.75x0.028)x 30.25 = (sxs)
And then square root to get the s

Answer 2

Answer: About 58 miles per hour

Explanation:

Given: Police can estimate the speed of a vehicle before the brakes are applied using the formula :-

`0.75d=(s^2)/(30.25)`, where s is the speed in miles per hour and d is the length of the vehicle’s skid marks (feet).

Now, to find the approximate speed of a vehicle that left a skid mark measuring 150 feet, substitute d= 150 in the above formula we get

`0.75(150)=(s^2)/(30.25)\\\\\Rightarrow\ s^2=0.75(150)(30.25)\\\\\Rightarrow\ s^2=3403.125\approx3403\\\\\Rightarrow\ s=√(3403)=58.3352380641\approx58`

Hence, the approximate speed of a vehicle that left a skid mark measuring 150 feet = 58 miles per hour .