Find the distance from A to the centroid of the triangle. A(2,3/2,-4), B(3,-4,2), C(1,3,-7).
Another approach . . .
Find the distance from A to the centroid of the triangle
with vertices: .
You are expected to know that the centroid is the common intersection of the medians.
Also, the centroid is the distance from a vertex to the midpoint of the opposite side.
The midpoint of side is: .
Distance is: .
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