The Equation of a Circle
Given a circle of radius r and centered at the point (h, k), the equation of the circle is:
[tex](x-h)^2+(y-k)^2=r^2[/tex]
Please, note the value of the coordinates of the center appear with its signs changed.
We have to find the equation of this circle by substituting the values of r = 3 and (h, k) = (2, -3). Substituting:
[tex]\begin{gathered} (x-2)^2+(y+3)^2=3^2 \\ \text{Operating:} \\ (x-2)^2+(y+3)^2=9 \end{gathered}[/tex]
Choice C.
