If a $\triangle ABC$ has vertices $A ( - 1,7 ) , B ( - 7,1 )$ and $C ( 5 , - 5 )$, then its orthocentre has coordinates:\\
(1) $( - 3,3 )$\\
(2) $( 3 , - 3 )$\\
(3) $\left( - \frac { 3 } { 5 } , \frac { 3 } { 5 } \right)$\\
(4) $\left( \frac { 3 } { 5 } , - \frac { 3 } { 5 } \right)$