Answer:
bearing of A from C is - 65.24°
the distance |BC| is 187.84 m
Step-by-step explanation:
given data
girl walks AB = 285 m (side c)
bearing angle B = 78°
girl walks AC = 307 m (side a)
solution
we use here the Cosine Law for getting side b that is
ac² = ab² + bc² - 2 × ab × cos(B) ...............1
307² = 285² + x² - 2 × 285 cos(78)
x = 187.84 m
and
now we get here angle θ , the bearing from A to C get by law of sines
sin (θ) =
sin (θ) = 0.5985
θ = 36.76°
and as we get here angle BAC that is
angle BCA = 180 - ( 36.76° + 78° )
angle BCA = 65.24°
and here negative bearing of A from C so - 65.24°