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Silent_Sorrow
Let A = (−1, 2, 1), B = (−7, 0, 1), C = (−3,−2,−3). How do you determine if the triangle ABC is right angled? Is it isosceles?
For a triangle be right you must multiply any two vectors. Try multiply A*B. If the product is zero, then the triangle is right.
So I first find the dot product of AB and BC?
also you could find the length of the edges and see if it satifies pathagorean theorem