Find the circumference

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A,B,C, are points on the circle. Point D is the center of the circle. Chord AB is $6\sqrt{2}$. Segment AB and Segment BC is perpendicular.

Can I find the circumference of the given circle, using the given information above only?

I tried this problem, but I made a conclusion that I need an extra piece of information. How do you guys think?

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$AB \perp BC$ doesn't tell us anything. That would be true of any circle (assuming that $A,D,C$ are colinear and $D$ is the center [so $ADC$ is a diameter).

So all this tells us is that the circle has a chord of $6\sqrt 2$ but any circle with a diameter of $6\sqrt 2$ will have a chord of $6\sqrt 2$ so all we can conclude is the diameter is at least $6\sqrt 2$.

If we know some more information such as $AC\perp DB$ or $AB = BC$ (btw $AC\perp DB \iff AB=BC$) then we could solve it. Are you sure the problem was written correctly? Perhaps the book mad an error and we were suppose to be told $AD \perp DB$?

If that were the case then as $AD,DB, DC$ are equal length radii and $\triangle ADB$ is right triangle we have $AD^2 + DB^2 = (6\sqrt 2)^2$ and that's easily solved that $AD = 6$.

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You are correct. You know that AC is a diameter but ABC could be a right triangle of any proportion between the legs. The drawing seems to have AB=BC but you are not given that.