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A man standina on tha clackukich is r above the wateyuaLi GOa hill as Gos andkandanrSS OAhill as 30 Final the aistanes l tienitihil |
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Answer» Let a man is standing on the Deck of a ship at point a such that AB = 10 m & let CE be the hill Thus, AB = CD = 10 m The top and bottom of a hill is E and C. Given, the angle of depression of the base C of the hill observed from A is 30° and angle of elevation of the top of the hill observed from A is 60 ° Then ∠EAD= 60° &∠CAE= ∠BCA= 30°. (Alternate ANGLES) Let AD = BC = x m & DE= h m In ∆ ADE tan 60° = Perpendicular / base = DE/AD √3= h/x [tan 60° = √3] h = √3x……..(1) In ∆ ABC tan 30° = AB /BC [ tan30° = 1/√3] 1/√3 = 10/x x= 10√3 m.. …………..(2) Substitute the value of x from equation (2) in equation (1), we have h = √3x h= √3× 10√3= 10 × 3= 30 m h = 30 m The height of the hill is CE= CD+ DE= 10 +30= 40 m Hence, the height of the hill is 40 m & the Distance of the hill from the ship is 10√3 m. |
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