Question

A fighter jet F and a helicopter H leave the airport A at the same time. The jet flies 25 km on a bearing of 040° and the helicopter flies 30 km on a bearing of 320°. How far apart are the aircraft? (Use a scale of 1 cm to represent 5 km.)

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Answer 1

FH = 35.64

Explanation:

(∠A = 360 so the other angle is 40)

By law of cosines,

FH² = AH² + FA² - 2(AH)(FA) * cos(A)

= 30² + 25² - 2(30)(25) * cos(80)

= 900 + 625 - 1500 * 0.17

= 1525 - 255

FH² = 1270

FH = √1270

FH = 35.64