Verified Answer :

so this equation will be 

x^2 +y^2 = 16^2

hope this will help you

Answer: The equation of the circle is \(x^2+y^2=256.\)

Step-by-step explanation:  We are given to find the equation of a circle whose center is at the origin and whose radius is 16 units.

The standard equation of a circle with center at (g, h) and radius 'r' units is given by

\((x-g)^2+(y-h)^2=r^2.\)

According to the given information,

Center is at the origin (0, 0), so, (g, h) = (0, 0),

and radius, r = 16.

Therefore, the equation of the circle is given by

\((x-0)^2+(y-0)^2=16^2\\\\\Rightarrow x^2+y^2=256.\)

Thus, the required equation of the circle is \(x^2+y^2=256.\)