Answer:
BC ≈ 370 m
Step-by-step explanation:
Using the Cosine rule in Δ ABC
a² = b² + c² - 2bccosA
= 450² + 220² - (2 × 450 × 220 × cos55°)
= 202500 + 48400 - 198000cos55°
= 250900 - 113568.1344
= 137331.8656 ( take square root of both sides )
a = [tex]\sqrt{137331.8656}[/tex]
≈ 370.58314
Then BC ≈ 370 m ( to the nearest 10 m )
