SOLUTION: A car travels along a straight road at a speed of 5 km/h (kilometres per hour). Another car starts at the same time from the same point and travels along a perpendicular directio

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Question 948473: A car travels along a straight road at a speed of 5 km/h (kilometres
per hour). Another car starts at the same time from the same point
and travels along a perpendicular direction with speed 12 km/h.
When will the two cars be at a distance 65 km apart?

Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
A car travels along a straight road at a speed of 5 km/h (kilometres
per hour).
Another car starts at the same time from the same point
and travels along a perpendicular direction with speed 12 km/h.
When will the two cars be at a distance 65 km apart?
:
let t = time in hrs when they will be 65 km apart
then
5t = distance traveled by the first car (dist = speed * time)
and
12t = distance traveled by the 2nd car
:
This is a pythag problem, a^2 + b^2 = c^2, where:
a = 5t
b = 12t
c = 65
:
(5t)^2 + (12t)^2 = 65^2
25t^2 + 144t^2 = 4225
169t^2 = 4225
t^2 = 4225/169
t^2 = 25
t = sqrt%2825%29
t = 5 hrs for them to be 65 mi apart
:
;
Check this on your calc: enter sqrt%2825%5E2+%2B+60%5E2%29%29