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An observation tower is 75m high. A support wire is attached to the tower 20m the top. If the support wire and the ground form an angle of 46 degrees, what is the length of the support wire, to the nearest tenth?

User TheDiveO
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1 Answer

4 votes

Answer:

76.46m

Explanation:

Using what we know we can solve for the length of the support wire using Pythagoras.

Height of tower = 75m

Support wire 20 m from top

Angle formed (α) = 46°

Using Pythagoras :

Sinα = opposite / hypotenus

Height used = height of tower - 20 m from top

Height = opposite = (75 - 20)m = 55m

Hypotenus = Length of support wire

Sin 46 = 55m / hypotenus

Hypotenus * sin 46 = 55

0.71934 * hypotenus = 55

Hypotenus = 55/0.71934

Hypotenus = 76.458976

Hence, Lenght of support wire = 76.46 m

User Ted Lyngmo
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