Michael C. answered • 03/15/17

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Construct a trapezium, ABCD to represent this question;

AD and CB are parallel and horizontal, BD is vertical and represents the height of the plane, A and D are on the ground with the woman positioned at A.

angle DAB =ABC (Z angles) is 6 degrees, and DAC is 15 degrees, making BAC = 15-6 =9 degrees

distance travelled by the plane in 6 minutes BC, is 400*6/60 = 40 miles

using the sine formula AC/sine6 = CB/sine9 ; AC = 40 *0.1045/0.1564 = 26.73 miles

drop a vertical line from C to a point X on AD; CX = BD (opposite sides of a rectangle)

CX/AC = sine15; therefore CX = 26.73 * 0.2588 = 6.92 miles = BD, or the height of the plane.

Hence the height of the plane is

**6.92 miles**
Alondra G.

03/15/17