SOLUTION: The formula d = 0.05s^2 + 1.1s estimates the minimum stopping distance d in feet for a car traveling s miles per hour. a. a car traveling at 60 miles per hour, how many feet doe

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Question 133136: The formula d = 0.05s^2 + 1.1s estimates the minimum stopping distance d in feet for a car traveling s miles per hour.
a. a car traveling at 60 miles per hour, how many feet does this car need to safely stop?
b. What is the maximum speed a car can be traveling if it has only 50 feet to stop?
Thank you for your help.
Answer by checkley71(8403) About Me  (Show Source):
You can put this solution on YOUR website!
d=.05s^2+1.1s
d=.05*60^2+1.1*60
d=.05*3600+66
d=180+66
d=246 feet to stop when traveling 60 mph.
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50=.05s^2+1.1s
.05s^2+1.1s-50=0
using the quadratic equation:x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+ we get:
s=(-1.1+-sqrt[1.1^2-4*.05*-50])/2*.05
s=(-1.1+-sqrt[1.21+10])/.1
s=(-1.1+-sqrt11.21)/.1
s=(-1.1+-3.348)/.1
s=(-1.1+3.348)/.1
s=(-1.1+3.348)/.1
s=2.248/.1
s=22.48 mph is the max speed for a 50 foot stopping distance.