here it is... A fence 3 feet tall runs parallel to a tall building at a distance of 6 feet from the building. What is the length of the shortest ladder that will reach from the ground over the fence to the wall of the building? [Hint: Determine the length of a ladder that touches the building, fence, and ground as a function of the acute angle the ladder makes with the ground.]
Well, if you draw two triangles : one from the top of the fence to the wall and one from the ground to the top of the fence, they both have angle p and the length of one hypotenuse is 6/cosp and the other 3/sinp. Total length 6/cosp + 3/sinp Or you could have 6/sin(90-p) and 3/sinp which might be easier? Sorry I can't help more. It might help you to know that sinx/cosx = tanx for rearranging and stuff.