Question

Find the equation of the circle in standard form for the given center (h,k) and radius r: (h,k)=(0,0), r=9

Answer 1

x^2 + y^2 = 81 is the equation of a circle you specified

Answer 2

Answer: $x^2+y^2=81$

Step-by-step explanation:

The equation of circle ( in general form ) is  given  by :_

$(x-h)^2+(y-k)^2=r^2$

, where r= radius of the circle .

(h,k) = center of the circle .

Given : Center = (h,k)= (0,0)

Radius = r = 9 units

Then the equation of the circle will be :-

$(x-0)^2+(y-0)^2=(9)^2$

$\Rightarrow x^2+y^2=81$

Hence, the required equation of the circle  = $x^2+y^2=81$