SOLUTION: The braking distance D in feet required to stop a car traveling x miles per hour on​ dry, level pavement can be approximated by Upper D equals one sixteenth x squared D= 1

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Question 1080912: The braking distance D in feet required to stop a car traveling x miles per hour on​ dry, level pavement can be approximated by Upper D equals one sixteenth x squared D=
1
16x2.
​(a) Calculate the braking distance for 3030 miles per hour and 7070 miles per hour. How do your answers​ compare?
​(b) If the braking distance is 4949 ​feet, estimate the speed of the car.
​(c) Use a calculator to solve part​ (b) numerically. Do your answers​ agree?

Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
The braking distance D in feet required to stop a car traveling x miles per hour on dry, level pavement can be approximated by Upper D equals one sixteenth x squared: D = 1%2F16x^2.
(a) Calculate the braking distance for 30 miles per hour and 70 miles per hour. How do your answers compare?
D = 1%2F16*30^2
D = 900%2F16
D = 56.25 ft
&
D = 1%2F16*70^2
D = 4900%2F16
D = 326.67ft
:
(b) If the braking distance is 49 feet, estimate the speed of the car.
Estimate 27 mph
(c) Use a calculator to solve part (b) numerically. Do your answers agree?
1%2F16x^2 = 49
x^2 = 49 * 16
x = sqrt%28784%29
x = 28 mph