When graphing a circle, the following formula is used:
[tex](x - h)^{2} + (y - k)^{2} = r^{2}[/tex]
h and k refer to the center of the circle, which is found at (h,k).
To find the radius of the circle, square root the right side:
[tex]\sqrt{16} = 4[/tex]
The radius of the circle is 4 units.
Look at the equation to find h and k. There is no h value represented, so h will equal 0. 10 is subtracted from y, so k is 10. The center of the circle is at (0,10).
