Question

What is the general form of the equation of a circle with a center at the origin and a radius of 9? (2 points)

x^2 + (y - 9)^2 = 1

(x - 9)^2 + y^2 = 1

x^2 + y^2 = 9

x^2 + y^2 = 81

Answer 1

for x^2 + (y - 9)^2 = 1
(0,9) , r =1
for (x - 9)^2 + y^2 = 1
(9,0) , r =1
for x^2 + y^2 = 9
(0,0) , r =3
for x^2 + y^2 = 81
(0,0) , r = 9

Answer 2

the general equation of any circle is
(x-a)^2+(y-b)^2=r^2
where
(a,b)=the center coordinates
r=the radius

Answer 3

Ohh Okay , I Understand , Thanks Guys @esamalaa @hazem-wardat