Hi,

The standard equation of a circle with center C(h,k) and radius r is :



Find the radius

completing the squares

x^2+y^2+12x+8y+16=0

(x+6)^2 + (y+4)^2 -36 -16 +16 = 0

(x+6)^2 + (y+4)^2 = 36 = 6^2

radius is 6, the center of the circle (-6,-4)





 

RELATED QUESTIONS

Find the center of a circle defined by the equation :... (answered by Fombitz)

find the center of the circle defined by the equation 2x^2+2y^2+24x+28y+138=0.
I'm kinda  (answered by Fombitz)

Find the center and radius of the circle defined by the equation:

X^2+Y^2+4X-8Y+13=0

 (answered by josgarithmetic)

find the radius of the circle defined by the equation:... (answered by Fombitz,ewatrrr)

Find the radius of a circle defined by the equation:... (answered by solver91311)

Find the radius of the circle defined by the equation: 5x^2+5y^3+60x+40y+215=0.
It tells  (answered by Fombitz)

find the radius of the circle defined by the equation:... (answered by Jk22)

find the radius of the circle defined by the equation:... (answered by scott8148)

find the radius of a circle:... (answered by Earlsdon)