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The midpoint of AB is M(3,3). If the coordinates of A are (2,-8), what are the coordinates of B?

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Explanation:

MID POINT =[(X1 +X2)/2 , (Y1 +Y2)/2]

WE KNKW THAT A(2,–8) AND THE MID POINT IS (3,3)

SUBSTITUTING INTO THE EQUATION ABOVE

(3,3) = [(2+ X2)/2 ,(–8+ Y2)/2]

EQUATING THE X COORDINATES

=> 3 = (2+ X2)/2 (CROSS MULTIPLY)

=> 6 = 2 + X2

X(subscript 2)= 4

EQUATING THE Y COORDINATES

=> 3 =(–8 +Y2)/2 (CROSS MULTIPLY)

6 = –8 +Y2

=> Y(subscript 2)= 14

THEREFORE THE COORDINATES OF B ARE (4 ,14)

hope this helps :)

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