SOLUTION: Given an equilateral triangle with two vertices located at (-8, -5) and (3, 7), what is its perimeter?

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Question 887325: Given an equilateral triangle with two vertices located at (-8, -5) and (3, 7), what is its perimeter?
Answer by algebrapro18(249) About Me  (Show Source):
You can put this solution on YOUR website!
    Facts we will use:

      1) Equilateral triangles have all the same side lengths
      2) Perimeter of a triangle = the sum of all 3 side lengths
      = 3*one side length(from fact 1)
      3) The length of a side of a triangle is equal to the distance between the two vertices connected by that side.
      4) The distance between two points is d=sqrt%28%28x2-x1%29%5E2%2B%28y2-y1%29%5E2%29

      So we need to find the distance between the two given vertices and then multiply that by 3 to find the Perimeter(from facts above).

      Perimeter = 3*sqrt%28%28x2-x1%29%5E2%2B%28y2-y1%29%5E2%29
      = 3*sqrt%28%28-8-3%29%5E2%2B%28-5-7%29%5E2%29
      = 3*sqrt%28%28-11%29%5E2%2B%28-12%29%5E2%29
      = 3*sqrt%28121%2B144%29
      3*sqrt%28265%29