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Two walls on a city collapsed. The only solution found was attaching two ropes on each wall to hold each other, as in the image above. Knowing that the walls have 9 and 3 meters, find the height of the point which the two ropes cross.

 

 Jul 7, 2020
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Let the distance between the walls be  l

 

One rope goes from   y = 9 to 0   in length  l       now   let's also make l = 1 for convenience

  equation    y = -9/2x  +9  

 

other rope goes from 0 to 3   in lenght l (which is 1)

  equation   y = 3/2 x   

 

 

set them equal to find 'x'        3x = -9x+9         

                                               12x = 9

                                                 x = 3/4

 

now find the height by puttin 'x' into one of the equations      y = 3x = 3 * 3/4 = 9/4 meters high at cross

 Jul 8, 2020

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