Equation of a straight line passing through the point of intersection of x y 1 0 and 3x y 5 0 n...........

Equation of a straight line passing through the point of intersection of x -y + 1= 0 and 3x + y - 5 = 0 and perpendicular to one of them is

x + y+3 = 0

x + y - 3 = 0