$\"\"$

The standard form of the circle equation with center at the origin is $\"\"$ ,

where $\"\"$ is the radius of the circle.

The distance between the point $\"\"$ and the origin is equal to the radius of the circle.

Find the radius of the circle.

$\"\"$

Radius $\"\"$ . $\"\"$

Substitute $\"\"$ in $\"\"$ .

$\"\"$

The circle equation is $\"\"$ .

$\"\"$

The standard form of the circle equation is $\"\"$ .