Find the equation of the circle with center (1,2)(1, 2)(1,2) and touching the xxx-axis.
x2+y2−2x−4y+1=0x^2 + y^2 - 2x - 4y + 1 = 0x2+y2−2x−4y+1=0
x2+y2−2x−4y+4=0x^2 + y^2 - 2x - 4y + 4 = 0x2+y2−2x−4y+4=0
x2+y2+2x+4y+1=0x^2 + y^2 + 2x + 4y + 1 = 0x2+y2+2x+4y+1=0
x2+y2−1=0x^2 + y^2 - 1 = 0x2+y2−1=0