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3D Trig CSSA prelim problem (1 Viewer)

Aysce

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A vertical tower of height h metres stands on horizontal ground. From a point P on the ground due
east of the tower the angle of elevation of the top of the tower is 45°. From a point Q on the ground
due south of the tower the angle of elevation of the top of the tower is 30°. If the distance PQ is 40
metres, find the exact height of the tower.†

Please show working :) i tried it but didn't work out :/
 

funnytomato

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call the bottom of the tower point N
note: triangle PNQ is right angled
 

SpiralFlex

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I drew a nice pretty diagram for you.





First, we need to find . Since it's an isosceles triangle (both base angles of , hence both sides are equal), we know that is

Second we need to find an expression for





Use the power of pythagoras!





metres.
 
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funnytomato

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"You must spread some Reputation around before giving it to SpiralFlex again"


Edit: " a point P on the ground due east of the tower "
 
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Aysce

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Ahh i didn't see it from that perspective, thanks!
 

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