Equation of Normal for General Equation of a Circle

Q.

The normal to the circle $x^2+y^2+2x-10y+k$ = 0 which is perpendicular to x-3y+2=0 is

1. 3x+y=0

2. x+3y+2=0

3. 3x+y=2

4. 3x+y=4

Q. A circle touches all the four sides of a quadrilateral ABCD. Prove that AB + CD = BC + DA.