Question 1200552:  A triangle with vertices A(1, —5), B(—3, 0), and C(2, 3) is rotated 90° clockwise 
about vertex A. Find the co-ordinates of the image of vertex C. 
 Answer by greenestamps(13214)      (Show Source): 
You can  put this solution on YOUR website! 
  
The "path" from vertex A to vertex C is "up 8, right 1".
  
When the triangle is rotated 90 degrees clockwise about vertex A, "up 8, right 1" becomes "right 8, down 1".
  
So the image of vertex C is 8 units right and 1 unit down from vertex A.
  
ANSWER: (1+8,-5-1) = (9,-6)
  
Depending on your level of math knowledge, you could of course work this problem formally using vectors....
  
 
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