please help asap. this circle is centered at the origin and the length of its radius is 8. what is the circles equation
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Answer: [tex]x^2 + y^2 = 64[/tex]
Step-by-step explanation:
Since, the equation of a circle that having the center (h,k) and radius r is,
[tex](x-h)^2 + (y-k)^2 = r^2[/tex]
Here the circle is centered at the origin,
That is, h = 0 , k = 0
Also, the radius of the circle is 8,
That is, r = 8 unit,
Thus, the equation of the given circle,
[tex](x-0)^2 + (y-0)^2 = 8^2[/tex]
[tex]x^2 + y^2 = 64[/tex]