Geometryeasy · Past Paper
The equation x^2 + y^2 + 2gx + 2fy + c = 0 represents a circle. Its radius is given by:
Asqrt(g + f - c)
Bsqrt(g^2 + f^2 - c)
Cg^2 + f^2 - c
Dsqrt(g^2 + f^2 + c)
✓ Correct Answer: B — sqrt(g^2 + f^2 - c)
This is the standard formula for the radius of a circle in general form.
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