Q9 of 12 Page 203

At the foot of the mountain, the elevation of its summit is 45°, after ascending 1000m towards the mountain up a slope of 30°, inclination the elevation found to be 60°. Find the height of the mountain.

The figure is given below:



height of mountain = CD = H


In ΔACD,





⇒ DC = AC = H


In ΔEAB,



y


Thus, BC = AC – AB = (H–500)m





⇒ AB = 500√3m


thus BC = AC – AB = (H – 500√3)m


thus EF = (H–500√3)m (since BC = EF)


In ΔDEF,









H = 1350 m


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7

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 8

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 11

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