Answer:
523.8 miles
Step-by-step explanation:
The drawing attached represents the question. We create a triangle with the distances from each pair of cities, and we call the distance from B to C by 'd'.
First, we need to find the angle BAC:
55° + BAC + 7° = 90°
BAC = 28°
Then, we can use the law of cosines to find the value of d:
d^2 = 470^2 + 890^2 - 2*470*890*cos(BAC)
d^2 = 470^2 + 890^2 - 2*470*890*0.8829
d^2 = 274365.86
d = 523.8 miles