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Preliminary mathematics marathon (2 Viewers)

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Please say how long your working out was.
No working out, I just drew the triangle and used a calculator to do sine rule :lol:

Anyone know where to find more of these contruction questions?
A tree stands at the north bank of a river with straight parallel banks running east to west. The angle of elevation to the top of a tree is 28° when measured from point A on the south bank and distant 3 metres to the west of the tree. From another point B on the south bank and distant 5 metres to the east of the tree, the angle of elevation of the tree is 19°. From a point half-way between A and B, find the angle of elevation of the top of the tree.
 
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hscishard

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No working out, I just visualised the triangle in my head and used a calculator to do sine rule :lol:



A tree stands at the north bank of a river with straight parallel banks running east to west. The angle of elevation to the top of a tree is 28° when measured from point A on the south bank and distant 3 metres to the west of the tree. From another point B on the south bank and distant 5 metres to the east of the tree, the angle of elevation of the tree is 19°. From a point half-way between A and B, find the angle of elevation of the top of the tree.

Don't get the question. Is this 3d Trig?
 
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Here's a diagram:



The question asks you to find the angle of elevation of the tree from the midpoint of AB.
 
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It's in 3D, the two horizontal lines are the parallel river banks, the line going upwards is the tree.
 
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Oh wait, read the question wrong, it says find the angle of elevation of the tree from the south bank due south of the tree between A and B.
 
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Wha? Whered the 90 come from?
Wtf..how is that the mindpoint.

I like the minus part
Oh wait, read the question wrong, it says find the angle of elevation of the tree from the south bank due south of the tree between A and B.
Haha yeah the minus, I was like how the fuck can they relate? And then I realised w was common.
 

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