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Triangle Perimeter

Also known as perimeter of a triangle · sum of the sides

P=a+b+cP = a + b + c

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Add the three sides. The only subtlety is which triples are legal: the triangle inequality demands that each side be shorter than the sum of the other two, so 2, 3, and 10 cannot close into a triangle no matter how you arrange them. Given a perimeter and two sides, the third follows by subtraction — the surveyor's way of closing a traverse.

Triangle Perimeter
P=a+b+cP = a + b + c
Where
  • PP= Perimeter
  • aa= Side a
  • bb= Side b
  • cc= Side c
Missing one of these? Work it out first, then come back