Question

Two planes leave the same airport at the same time. One flies at 20° east of north at 300 miles per hour. The second flies at 40° east of south at 400 miles per hour. How far apart are the planes after 2 hours? (Round your answer to the nearest mile.)

Answer 1

This is a side - angle - side problem, solve using the law of cosines:

a^2 = 600^2 + 800^2 - 2*600*800*cos(120)

a = 1216.55 = 1,217 miles apart.