Question

In a tournament, a professional golfer knows that she is 200 yards from the hole. A spectator is watching her play and is 140 yards away from the golfer.
If the spectator has an angle of 115° between the golfer and the hole, what is the angle that the golfer has between the spectator and the hole?

hole?

25.6°
39.4°
64.3°
65.0°

Answer 1

Answer:

28.9°

Step-by-step explanation:

The golfer, hole, and spectator form a triangle. Let ABC be the triangle and let the angle the spectator has between the golfer and the hole be A = 110°, the angle the golfer has between the spectator and the hole be B, and the angle the hole has between the golfer and the spectator be C. Let the angle between the golfer and the hole be a = 200 yards, the distance between the spectator and the hole be b and the distance between the golfer and the spectator be c = 140 yards,

Using the sine rule for the triangle, we find angle C.

So, a/sinA = b/SinB = c/SinC

So, a/sinA = c/sinC

sinC = csinA/a

C = sin⁻¹(csinA/a)

Substituting the values of the variables into the equation, we have

C = sin⁻¹(csinA/a)

C = sin⁻¹( 140sin110°/200)

C = sin⁻¹( 7 × 0.9397/10)

C = sin⁻¹(6.5778/10)

C = sin⁻¹(0.65778)

C = 41.13°

We know that A + B + C = 180°  (sum of angles in a triangle)

And since the angle, the golfer has between the spectator and the hole be B

So, B = 180° - (A + C)

B = 180° - (110° + 41.13°)

B = 180° - 151.13°

B = 28.87°

B ≅ 28.9°