Speed and miles

Question

Part 2: Police departments find it very useful to be able to approximate driving speeds in skidding accidents. If the road surface is wet concrete, the function S(x)= √10.5x is used, where S(x) is the speed of the car in miles per hour and x is the distance skidded in feet. Find how fast a car was moving if it skidded 116 feet on wet concrete and how far it would skid if it was travelling at 45 miles per hour.

Answer 1

speed = sqrt( 10.5*116) is almost 35 mph

45 = sqrt( 10.5x)

2025 = 10.5x

x = 2025/10.5 = 192 and 7/6 ft skid mark