Question 863133
what is the perimeter of a triangle with vertices at (1,1), (-1,5) and (1,7)
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Label the points A(1,1), B(-1,5) and C(1,7)

Find the distance between the points.
{{{AB = sqrt(diffy^2 + diffx^2) = sqrt(4^2 + 2^2) = sqrt(20)}}}
Find BC and AC the same way.
Add them.