1-5 Find the coordinates of the center and the measure of the radius for a circle whose equation is, 1. (x-8)^2+(y+4)^2=12
2. (x+8)^2+(y-8)^2=81
3. x^2+(y-5)^2=9
4. (x+4))^2+(y+5)^2=64
5.(x-7)^2+(y-3)^2=144
6. Write the equation of a circle whose center is (0, -5) and radius is 7.
7. Write the equation of a circle whose center is (6, -1) and diameter is 12.
8. Write the equation of a circle whose center is (-2, 3) and radius is 4.
9. Find the radius of a circle whose center is (0,3) and a y-intercept of (0,7).