Coordinates

Suppose P is the point (5,3) and Q is the point (6,-3). Find point T such that Q is the midpoint of segment PT.    

Since Q is the midpoint, Q to P is the same distance as Q to T.    

To get from Q to P, aka from (6, –3) to (5, 3), you go left 1 and up 6    

To get from Q to T, go the same distances except in the other direction.    

So from (6, –3) go right 1 and down 6 to (7, –9) and that's where T is.    

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