Answer:
See below.
Step-by-step explanation:
The equation for a circle is:
[tex](x-h)^2+(y-k)^2=r^2[/tex]
Where (h,k) is the center and r is the radius.
From the graph, we can see that (0,0) is the center.
Thus, h=0 and k=0:
[tex]x^2+y^2=r^2[/tex]
From the graph, we can also see that the radius is 3 as (-3,0) and (3,0) are points on the circle.
Thus, r=3, and r^2=9.
The equation is:
[tex]x^2+y^2=9[/tex]
