# write the equation of a circle with center at (a,b) and passing through the origin. geometry The circle we have to determine has its center at ( a, b) and passes through the origin. The radius of the circle is the distance between the points (0,0) and (a, b)

The radius is sqrt ( a^2 + b^2)

The equation of a circle with center ( a,...

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The circle we have to determine has its center at ( a, b) and passes through the origin. The radius of the circle is the distance between the points (0,0) and (a, b)

The radius is sqrt ( a^2 + b^2)

The equation of a circle with center ( a, b) and radius r is given by:

(x - a)^2 + ( y - b)^2 = r^2

Substituting the values we have:

(x - a)^2 + ( y - b)^2 = a^2 + b^2

=> x^2 + a^2 - 2ax + y^2 + b^2 - 2by = a^2 + b^2

=> x^2 + y^2 - 2ax - 2by = 0

The required equation of the circle is x^2 + y^2 - 2ax - 2by = 0

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