SOLUTION: A plane leaves the airport flying at 180 mph with a heading of 70 degrees. One hour later a second airpirt flying at 220 mph leaves the same airport with a heading of 345 degrees.

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Question 720171: A plane leaves the airport flying at 180 mph with a heading of 70 degrees. One hour later a second airpirt flying at 220 mph leaves the same airport with a heading of 345 degrees. How far apart are the airplanes at 1.5 hours after the first airplane leaves the airport?
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
A plane leaves the airport flying at 180 mph with a heading of 70 degrees.
One hour later a second airplane flying at 220 mph leaves the same airport with a heading of 345 degrees.
How far apart are the airplanes at 1.5 hours after the first airplane leaves the airport?
:
The angle between the two aircraft (360-345) + 70 = 85 degrees
:
We can use the law of cosines here: a^2 = b^2 + c^2 - 2(b*c)cos(A)
Where
a = the distance apart after 1.5 hrs
b = 1.5(180) = 270 mi from the airport at this time
c = .5(220) = 110 mi from the airport at this time (left one hr later)
A = 85 degrees
;
a^2 = 270^2 + 110^2 - 2(270*110)*cos(85)
I'll let you do the math here, I got about 282.5 mi