Aashay94 wrote:
Maybe I'm not understanding the logic here correctly. Let's tweak the question and say that we had sides with lenghts 7, 3 and D.
By this formula, (7-3)<D<(7+3) -> 4<D<10.
4 now falls out of range. Can someone explain? Thanks!
Hi Aashay94,
This type of situation is based on the Triangle Inequality Theorem. The simple idea behind this math rule is that when you are forming triangles and have the values of two of the sides, you can determine the 'range' of values for the third side.
The smallest POSSIBLE length for the third side must be greater than the 'positive difference' of the two sides that you have.
The largest POSSIBLE length for the third side must be less than the sum of the two sides that you have.
Thus, with sides of 3, 7 and D....
The smallest possible distance is GREATER than (7 - 3) = 4
The largest possible distances is LESS than (7 + 3) = 10
Thus 4 < D < 10.
The same concept applies to the question at the beginning of this thread (changes the values to 3, 4 and D and you'll see).
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