Question

Dimitri has let out 40m of his kite string, which makes an angle of 72° with the horizontal ground. If the kite flies directly over Sarah's head, what is the distance between Dimitri and Sarah?

Answer 1

Check the picture below.

`\cos(72^o )=\cfrac{\stackrel{adjacent}{ds}}{\underset{hypotenuse}{40}} \implies 40\cos(72^o)=ds \implies 12.36\approx ds`

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