Question

equaçao da circunferencia de raio 3 e centro 2,-5

Answer 1

Use o modelo:

$(x-x_C)^2+(y-y_C)^2=r^2\\ \\ (x-2)^2+(y-(-5))^2=3^2\\ \\ x^2-4x+4+y^2+10y+25=9\\ \\ \boxed{x^2+y^2-4x+10y+20=0}$