(1) first of all , get the midpoint which is (4,4) , then find the line perpendicular which passes through the midpoint . The gradient of this line would be 1 so the gradient of the line perpendicular to this line = -1 ,
(2) Focus , F=(0,4) so we know that the parabola is in the form of , vertex is 0 so the equation would be .
(3) The general equation is given by
where the radius would be (-g,-f) and the radius
so for this question , 2g=-10 , g=-5 and 2f=4 , f=2
centre =(5,-2) and radius