Q52 of 68 Page 9

From the top and bottom of a building of height h, the angles of elevation of the top of a tower are α and β respectively. Prove that the height of the tower is

[Hint: Let AB be the tower and CD be the building. We draw CE AB. According to the question,


CD = h, ∠BDE = α, ∠BCA = β


Let AB =y


Then, BE = BA — EA =y— h


Let CA = x. Then DE =x


From right BDE, .....(i)


Also, from right BCA, .....(ii)


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