The equation of the circle in discuss whose center is at the origin and has radius; √5 is; x² + y² = 5.
The radius of the circle in discuss can be determined by evaluation as follows;
Radius = √((1-0)²+ (2-0)²)
Radius = √5.
Consequently, the equation of the circle whose center is at the origin and has a radius of √5 is;
(x-0)² +(y-0)² = √5.
x² + y² = 5.
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