Answer
(a). $(h,k)=(-\frac{1}{2},-\frac{1}{2}), r=1$.
(b). See graph.
(c). $(-\frac{1}{2}\pm\frac{\sqrt 3}{2},0)$, $(0,-\frac{1}{2}\pm\frac{\sqrt 3}{2})$.
Work Step by Step
(a). $x^2+y^2+x+y+\frac{1}{4}+\frac{1}{4}=\frac{1}{2}+\frac{1}{4}+\frac{1}{4}\longrightarrow (x+\frac{1}{2})^2+(y+\frac{1}{2})^2=1$, thus $(h,k)=(-\frac{1}{2},-\frac{1}{2}), r=1$.
(b). See graph.
(c). For x-intercept(s), let $y=0$, we get $(-\frac{1}{2}\pm\frac{\sqrt 3}{2},0)$, for y-intercept(s), let $x=0$, we get $(0,-\frac{1}{2}\pm\frac{\sqrt 3}{2})$.
