Answer:
(i) The distance between B and C is approximately 552.9 m
(ii) ∠ACB is approximately 40.49°
(iii) The bearing of C from B is approximately 184.49°
(iv) The shortest distance from A to BC is approximately 331.155 m
Explanation:
The given parameters are;
The length of segment AB = 370 m
The length of segment AC = 510 m
The bearing of B from A = 68°
The bearing of C from A = 144°
(i) From the bearing of B from A = 68° and the bearing of C from A = 144°, we have;
∠BAC = 144° - 68° = 76°
∠BAC = 76°
Let A represent ∠BAC, c represent segment AB, b represent segment AC, and a represent segment BC, by cosine rule, we have;
a² = b² + c² - 2·b·c·cos(A)
By substituting the known values, we get;
a² = 510² + 370² - 2 × 510 × 370 × cos(76°)
a² ≈ 397000 - 91301.3234 ≈ 305698.677
BC = a ≈ √(305,698.677) ≈ 552.9
The distance between B and C, BC ≈ 552.9 m
(ii) By sine rule, we have;
a/(sin(A) = b/(sin(B)) - c/(sin(C))
Therefore;
552.9/(sin (76°)) = 370/(sin(C))
sin(C) = 370/(552.9/(sin (76°))) ≈ 0.649321
C = arcsine(0.649321) ≈ 40.49°
∠C = ∠ACB ≈ 40.49°
(iii) Angle ∠B = ∠ABC = 180° - 76° - 40.49° ≈ 63.51°
The bearing of A from B = 360° - (180° - 68°) = 248°
Therefore, the bearing of C from B ≈ 248° - 63.51° ≈ 184.49°
(iv) The shortest distance from A to BC = 370 m × sin(63.51°) ≈ 331.155 m