Answer:
69.94 miles
Step-by-step explanation:
The distance d₁ the first ship moves after 3 hours is 3 hours × 15 miles per hours = 45 miles
The distance d₂ the second ship moves after 3 hours is 3 hours × 12 miles per hours = 36 miles.
The angle the first ship's direction makes in the North-East direction is 90° - 75° = 15°
The angle the second ship's direction makes in the South-West direction = 14°
The distance moved by the two ships form the side of a triangle. The angle, θ between the two ship directions is 14° + 90° + 15° = 119°
Using the cosine rule, we find the distance d between the two ships
d = √(d₁² + d₂² -2d₁d₂cosθ)
= √(45² + 36² -2×45×36cos119°)
= √(2025 + 1296- (-1570.78))
= √(3321 + 1570.78)
= √4891.78
= 69.94 miles
