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    Basically i'm doing a level maths. The question I have is one with sun angles. There are two triangles and we have to use the sin rule to work out the length of a triangle side - I know all three angles in the first triangle.

    However, i'm only told that one of the sides is a nM shorter than another side on the other triangle. What do I do with this information to calculate this unknown length?
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    Anyone? I know it's stupid but please help.
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    Can you post a picture with a diagram. I don't think what you're asking is very clear.
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    I don't want to post a picture. Basically we have been told that the sun casts a shadow on a tower at two different lengths from the tower e.g 40 degrees at ob and 10 degrees at oc

    We are then told that oc is 120m longer than ob. And asked to work out the length of ob and the height of the tower.

    I've been told that we are supposed to do pythagoras but I don't know how to do it with just one length.

    http://gogeometry.com/problem/p363_r...nce_angles.htm
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    Anyone? I really want this done
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    (Original post by Frostyjoe)
    Anyone? I really want this done
    (Thread was in the wrong forum - has now been moved to maths).

    I can't see Pythagoras being terribly useful.

    If we call the height of the tower y, and the distance OB, x.

    Then considering the triangle with base OC, we have:

    y = (120+x) tan 10

    We can do something similar with the smaller triangle

    y=....

    Equate and solve.
 
 
 
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