Question

Origin is the centre of circle passing through
the vertices of an equilateral triangle whose
median is of length 3a then equation of the
circle is
1) x² + y2 = a? 2) x² + y2 = 2a
3) x² + y2 = 3a? 4) x² + y2 = 4a​

Answer 1

Answer:

Equation of a circle passing through the origin is x2+y2=a2

If the centroid of the triangle with the centre of the circle, then the radius of the circle is 32 of the length of the median

∴r=32×3a

⟶r2=4a2

∴x2+y2=4a2