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    Hi!

    I have the following question which I have failed to solve:

    Three towns A, B and C lie on a straight road running east from A. B is 6 km from A and C is 22 km from A. Another town D lies to the north of this road and it lies 10 km from both B abd C. Calculate the distance of D from A and the bearing of D from A. :cool:
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    (Original post by salem)
    Hi!

    I have the following question which I have failed to solve:

    Three towns A, B and C lie on a straight road running east from A. B is 6 km from A and C is 22 km from A. Another town D lies to the north of this road and it lies 10 km from both B abd C. Calculate the distance of D from A and the bearing of D from A. :cool:
    Just draw a picture and you find:

    AD = sqrt(14^2+6^2)=sqrt(232)

    I am not sure what you mean by bearing.
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    (Original post by way2go)
    Just draw a picture and you find:

    AD = sqrt(14^2+6^2)=sqrt(232)

    I am not sure what you mean by bearing.
    bearing is the angle from north.
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    (Original post by salem)
    Hi!

    I have the following question which I have failed to solve:

    Three towns A, B and C lie on a straight road running east from A. B is 6 km from A and C is 22 km from A. Another town D lies to the north of this road and it lies 10 km from both B abd C. Calculate the distance of D from A and the bearing of D from A. :cool:
    try using pythagaros' theourum instead of trig...

    G
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    (Original post by salem)
    Hi!

    I have the following question which I have failed to solve:

    Three towns A, B and C lie on a straight road running east from A. B is 6 km from A and C is 22 km from A. Another town D lies to the north of this road and it lies 10 km from both B abd C. Calculate the distance of D from A and the bearing of D from A. :cool:

    Sorry not to spoonfeed you but have you tried drawing a little sketch? Here are a couple of hints:

    Triangle BCD is isosceles.
    Make sure you know the cosine rule.


    J.
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    (Original post by salem)
    Hi!

    I have the following question which I have failed to solve:

    Three towns A, B and C lie on a straight road running east from A. B is 6 km from A and C is 22 km from A. Another town D lies to the north of this road and it lies 10 km from both B abd C. Calculate the distance of D from A and the bearing of D from A. :cool:
    First thing to do is construct a diagram of the problem.

    A, B and C should be on a straight line. Since D is the same distance from B and C this should tell you that BCD is an isosceles triangle. It will also be helpful to split this triangle down the middle so you get a right angled triangle. You can then use Pythagoras' theorem to find the length of AD. From this, you can get the bearing.

    Good luck
 
 
 
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