Question 619433
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Hi,
 x^2+y^2+6x+8y+9=0
 (x+3)^2 - 9  + (y+4)^2  - 16 + 9
 {{{(x+3)^2 + (y+4)^2 = 16 = 4^2}}}   C(-3,-4)  and r = 4