Word Problem

Question

The equation s=2√5x can be used to estimate the speed, s, of a car in miles per hour, given the length in feet, x, of the tire marks it leaves on the ground. A car traveling 60 miles per hour came to a sudden stop. According to the equation, how long would the tire marks be for this car?

I need the steps, along with the answer for this problem please

Answer 1

though the equation is not clearly written, it must be that the x is outside of the radical, as solving the equation with the x inside the radical produces a nonsensical solution

 

POINT: no car can come to a stop in zero seconds; the absence of the time frame makes it impossible to clear the units properly, so we will have to ignore them

 

1. convert 60m/h to feet/sec = (60m/hr*5280ft/mi)/3600sec/hr=88ft/sec

 

2. substitute 88ft/sec for s

 

3. 88ft/sec = 2√5x 

 

4. 88/2√5 = 88/4.4 = 19.6ft