The form of the equation of the circle is
[tex](x-h)^2+(y-k)^2=r^2[/tex](h, k) is the center
r is the radius
Let us compare it with the given equation to find the center and the radius
[tex](x+1)^2+(y-1)^2=36[/tex]From the comparing
h = -1
k = 1
r^2 = 36
Find the square root of 36 to get r
[tex]\begin{gathered} r=\sqrt[]{36} \\ r=6 \end{gathered}[/tex]The center is (-1, 1) and the radius is 6