SOLUTION: Two cars leave a city at noon. One car travels north and the other travels east. Suppose the borthbound car is traveling at 60 mph, and the eastbound is traveling at 50 mph. Make a

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Question 243615: Two cars leave a city at noon. One car travels north and the other travels east. Suppose the borthbound car is traveling at 60 mph, and the eastbound is traveling at 50 mph. Make a table to show the distance between the 2 cars at 1 hour, 2 hours, 3 hours and "n" hours. Then, suppose that the northbound car is traveling at 40 mph and after 2 hours, the two cars are 100 miles apart. How fast is the other car going?
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
Two cars leave a city at noon. One car travels north and the other travels east.
Suppose the northbound car is traveling at 60 mph, and the eastbound is traveling at 50 mph.
:
This is a pythag problem, distance between the cars is the hypotenuse: a^2 + b^2 = c^2
n = no. of hrs traveled; a = 50n; b=60n
:
Make a table to show the distance between the 2 cars at 1 hour, 2 hours, 3 hours and "n" hours.
1 hr: sqrt%2850%5E2+%2B+60%5E2%29 = 78.1 mi
2 hr: sqrt%28%2850%2A2%29%5E2+%2B+%2860%2A2%29%5E2%29 = 156.2 mi
3 hr: sqrt%28%2850%2A3%29%5E2+%2B+%2860%2A3%29%5E2%29 = 234,3 mi
n hrs sqrt%28%2850n%29%5E2+%2B+%2860n%29%5E2%29 = sqrt%286100n%5E2%29 mi
:
Then, suppose that the northbound car is traveling at 40 mph and after 2 hours, the two cars are 100 miles apart.
How fast is the other car going?
Let a = 40*2, c=100, find b
80^2 + (2b)^2 = 100^2
6400 + 4b^2 = 100^2
4b^2 = 10000 - 6400
4b^2 = 3600
b^2 = 3600%2F4
b^2 = 900
b = sqrt%28900%29
b = 30 mph is the 2nd car
;
:
Check on a calc: enter sqrt%2880%5E2+%2B+60%5E2%29 = 100 mi