Given end points of diameter,
(x1,y1)=(-3,-4)
(x2,y2)=(0,0)
Now,
the equation of circle is,
(x-x1)(x-x2)+(y-y1)(y-y2)=0
or, (x+3)(x-0)+(y+4)(y-0)=0
or, x^2 +3x +y^2 +4y =0
or, x^2 +y^2 +3x + 4y=0
which is in the form of x^2 +y^2 +2gx +2fy + c=0
where,
g=3/2
h=2
c=0
Now,