Coordinate Geometry

If the vertices of a triangle are (9,9) (10, 1) and (6,7) , find the co-ordinates of its orthocentre.

(A) (9,9)
(B) (6,7)
(C)(4,5)
(D)(25/3, 17/3)

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Quant Question Of The Day: 112

Quant Question Of The Day: 111