Question

Calculate the length of edge AD in the triangle-based pyramid below.

Give your answer to 2 d.p.

Answer 1

Check the picture below.

`\tan(37^o )=\cfrac{\stackrel{opposite}{49}}{\underset{adjacent}{DB}}\implies DB=\cfrac{49}{\tan(37^o )} \\\\\\ \sin(56^o )=\cfrac{\stackrel{opposite}{DB}}{\underset{hypotenuse}{AD}}\implies AD=\cfrac{DB}{\sin(56^o )} \\\\\\ AD=\cfrac{ ~~ (49)/(\tan(37^o )) ~~ }{\sin(56^o )}\implies AD=\cfrac{49}{\tan(37^o ) \sin(56^o )}\implies AD\approx 78.43`

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