1)Find the center & radius for the following

1. 2x^2+2y^2=72
2. (x-3)^2+(y-1)^2=4
3. (x-5)^2+(y+2)^2=49
4. (y-4)^2+(x-10)^2=64
5.(x^2-6x+9)+(y^2+8y+16)=1
6. x^2+12x+y^2-8y=-27
7. Write an equation for the circle with center at (3,-4) and with (2,-1) a point on the circle.