00:01
So in this problem, we have a plane that is traveling at 55 degrees.
00:08
And normally this would be a street line from c to b.
00:11
The destination is b at 400 miles, but the plane accidentally takes a detour and moves 55 degrees in a different direction.
00:20
And we're asked to find, so we end up with this triangle diagram here that represents a word problem.
00:26
And we're asked to find this red, the side length of the triangle that represents how far.
00:30
Away the plane is from the destination after 180 miles of going the wrong way.
00:36
And how many degrees in which direction should the plane now go to reach buffalo? so we're going to find the angle here and the side length here.
00:44
We're going to use the cosine, a lot of cosines, which says that c squared is equal to a squared plus b squared minus 2 times a b, cosine, which is c.
00:55
So c is equal to square root of a squared minus 2 times 180 times 400 times cosine and the angle is 55.
01:11
This is 4 cosine c.
01:13
We can plug this into our calculator.
01:16
So square root of 400 squared plus 180 squared minus 2 times 400 times 180 times 180 times cosine of 55.
01:25
And our answer is 331 .331 .4 miles...