Draw a right triangle. Label the height of the triangle. as 800 since the height of the triangle represents the height of the helicopter above the coast of the island. Label the base length of the triangle as d to represent the distance between the coast of the island and the coast of the mainland, P. The angle of depression from the helicopter to point P is 33° so draw a horizontal dotted line at the location of the helicopter and label the angle made by the horizontal line and the hypotenuse of the right triangle as 33°. The angle of elevation from P to the helicopter and the angle of depression from the helicopter to point P are congruent alternate interior angles so label the angle at P as 33°.
The side labeled 800 is opposite of P and the side labeled d is adjacent to P so you can use tangent to write an equation. Solve this equation for d and round to the nearest whole number.
The answer would be to divide 1030 by 50 and you would get 21 coaches not 20 because 50x20=1000 and there are 30 remainder. Therefor, you would need that extra coach with some seats left to spare. so your answer is 21 coaches