To find a line u need 2 things only..
here u can get slope and point.
as said perpendicular from A
perpendicular ot the line BC..
slope of BC (say m) = -5-4 / 2-(-3) = -9/5
slope of the line req. (say n) = 5/9 i.e (-1/m)
and the point is A..
get the line.