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Homework Help: Building hieght

  1. Mar 10, 2010 #1
    Hey guys!

    Me and all of my friends got this work for a mathematics question. But none of us can figure it out. We think they supplied too little information. We studying Engineering. I hope I posted it in the right place.

    1. The problem statement, all variables and given/known data

    The base of a building and the base of a tower are in the same horizontal plane. From the top of this building, the angle of elevation of the top of this tower is 10°. From a window 6m below the top of the building, the angle of depression of the base of the tower is 30°. The height of the tower is 120m.

    Determine the height of the building.

    Determine the distance between the building and the tower.

    2. Relevant equations

    Sine Rule and Cosine rule I figured... But there aint enough info to use ether.

    3. The attempt at a solution

    We basically drew it and filled in all the angles. One can find all the angles but with only one distance its pretty impossible to do anything else...

    Thanks in advance!
  2. jcsd
  3. Mar 10, 2010 #2
    You will have two unknown variables, x=distance between them and y=height of building. You also have two triangles that relate x and y in some way through angles. That will give you two equations.

    Two equations can solve two unknowns exactly, so it is solvable. You will first need to find those 2 equations. Then it is just a matter of messy algebra to get x and y.
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