An airplane flys at a constant altitude of 2 miles and a constant speed of 600 miles per hour on a straight course that will take it directly over a kangaroo on the ground. How fast is the angle of elevation of the kangaroo's line of sight increasing when the distance from the kangaroo to the plane is 3 miles? Give your answer in radians per minute.

Answer 1

Why are you posting this again ?
I answered your same question about 3 hours ago.
Always check back on your posts, mark their time, and they are easy to find that way.
http://www.jiskha.com/display.cgi?id=1412721979

Answer 2

The answer was wrong!

Answer 3

Did you try to find an error in my solution?
How do you know it is wrong?

Answer 4

The math looks good to me, but the negative answer is strange because the question was, how fast is the angle increasing?

That is because dx/dt = -600; the plane is approaching the kangaroo.

Hailey, did you do as Reiny asked, and check his math?

Answer 5

Yup, Steve is right, I had the plane flying away from the kangaroo, should have read it more carefully.
The numerical answer would simply change to a positive rate of change of the angle.

Answer 6

This answer is still incorrect. The 3 miles from the airplane to the kangaroo is the hypotenuse of the triangle. It is the shortest distance from the airplane to the kangaroo, not the horizontal distance.