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Math and Arithmetic

How do I find a missing diagonal in a rhombus?

Answer

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Wiki User
June 14, 2015 12:19PM

A rhombus has 2 diagonals and they are a straight lines drawn opposite to its interior corners intersecting each other at right angles.

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Wiki User
June 14, 2015 8:51AM

The answer depends on what information you do have about the rhombus. Assuming that you know the length of the sides and one of the diagonals, then,

  • In the triangle formed by the given diagonal and the sides of the rhombus, you know all three sides. So you can use the cosine rule to calculate the angle between the sides of the rhombus.
  • The other pair of angles in the rhombus are its supplement.
  • So now you know two sides and the included angle of the triangle formed by the missing diagonal and the sides of the rhombus.
  • You can use the cosine rule again to find the missing diagonal.