Exercise 9 Page 801

(x- h)^2+(y- k)^2= r^2 In this form, ( h, k) is the center of the circle and r is its radius. We are told that the center of the circle is ( 0, 3) and its radius is 7. This is enough information to write the equation. (x- 0)^2+(y- 3)^2= 7^2 ⇕ x^2+(y-3)^2=49