Answer:
center=(-5, -5)
radius=5
Explanation:
[tex]3x^2 + 3y^2 + 30x +30y+ 75 = 0\\\frac{3x^2 + 3y^2 + 30x + 30y+75 = 0}{3} \\x^{2} +y^{2} +10x+10y+25=0\\(x^{2} +10x)+(y^2+10y) =-25\\(x^{2} +10x+25)+(y^{2}+10y+25) =-25+25+25\\(x+5)^{2} +(y+5)^{2} =25\\[/tex]
[tex]center=(-5, -5)\\radius=5[/tex]
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