Find the value of p for which points (-5,1),(1,p), & (4,-1) are collinear.

Here is the link for the answer similar to your query:
https://www.meritnation.com/ask-answer/question/1-find-the-coordinates-of-circumcentre-of-a-triangle-whose/coordinate-geometry/6958322

Kindly refer the question(2) of above link.