Which equation is an equation of a circle with radius of 10 cm and center at (-3, 6)? a) (x + 3)^2 + (y - 6)^2 = 20b) ( x + 3)^2 + (y - 6)^2 = 100c) ( x - 3)^2 + (y + 6)^2 = 20d) (x - 3)^2 + (y + 6)^2 = 100 show your work