Complete the squares on the given equation to write it in the standard form of the equation of a circle. Remember that the standard form of the equation of a circle with radius r and center (h,k) is:

Additionally, remember that to complete the square of an expression, we can add and substract the necessary constants to make it look like a perfect square trinomial:

Starting from the given equation:

Add and substract 4 to complete the square of the x variable:

Add an substract 9 to complete the square of the y variable:

Therefore, the equation of the given circle in standard form, is:
