Question

A circle with center (1,2) passes through the point (0,6). Which of the following is the equation of the circle?

Answer 1

its either a or c  because of the factors x-1 and y-2

plug in the point  (0,6) to see which one fits 

equation a:-  
(0-1)^2 + (6-2)^2 =  1 + 16 = 17   but  equation a has ' = 36'

So its c