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A plane is 80 miles south and 95 miles east of an airport. How far is the plane from the airport? What bearing should be plane take to fly directly to the airport?

User Radim
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1 Answer

5 votes

Answer:

124.2 miles

∠310.1°

Explanation:

You want to know the bearing and distance to the airport from a plane that is 95 miles east and 80 miles south of it.

Distance

The Pythagorean theorem or the distance formula can be used to find the distance to the airport.

d = √((x2 -x1)² +(y2 -y1)²)

d = √((95 -0)² +(-80 -0)²) = √(9025 +6400) = √15425

d ≈ 124.197 . . . . miles

The plane is about 124.2 miles from the airport.

Bearing

The reference angle with respect to the +y axis can be found using the tangent relation.

Tan = Opposite/Adjacent

tan(α) = 95/80 = 19/16

α = arctan(19/16) ≈ 49.9° . . . . . . CCW from +y axis

The bearing angle is measured clockwise from the +y axis (north), so is ...

bearing = 360° -49.9° = 310.1°

The bearing to the airport is 310.1°.

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Additional comment

Some navigators would refer to the bearing as N 49.9° W.

Less commonly, it might be referred to as W 40.1° N. Usually, N and S are the reference directions, with the modification being E or W from there. The less common usage might be chosen if an angle less than 45° is wanted.

The bearing is often reported to the nearest degree, without any degree symbol, as N50W.

A plane is 80 miles south and 95 miles east of an airport. How far is the plane from-example-1
User Safa
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