A circle given by the x^2 + y^2 -2y -11 = 0, what is the value of K?
\
\ A circle given by
\
\ x^2 + y^2 -2y -11 = 0
\
\ can be written in standard form like this
\
\ x^2 + ( y - k)^2 = 12
\
\ What is the value of k in this eqation?

The circle equation is .

The standard form of circle equation is , where is center of circle and is radius of circle.

To change the expression into a perfect square trinomial add (half the y coefficient)² to each side of the expression.

.

Therefore, the value of is .