00:01
I've made a model of the situation.
00:03
P is where the plane is located.
00:04
3 % angle of depression is from the horizontal looking down to the airport, and we've got d the distance directly below the plane.
00:11
The plane is 30 ,000 feet high, and we want to find the distance from the point on the ground, d, to the airport, and calling it x.
00:20
Well, the angle of depression is the same as the angle of elevation, alternate interior angles.
00:26
So now we're inside of a right triangle, and we can use sokatoa, or trouble, or trouble.
00:31
And from that angle, we know the opposite...