how can i figure the center of a circle useing trig> geometry?

Question

any links to sites that might help as well?

Answer 1

fit any triangle inside the circle. the point where their verticies (the lines prependicular to the sides and starting from the middle) meet is the circumcenter of the triangle and therefore the center of the circle.

Answer 2

What information concerning the circle are you given?

If you are given no info, then draw a chord. Then draw the perpendicular bisector of that chord.

Now draw a different chord and its perpendicular bisector.

The two perpendicular bisectors will intersect at the center of the circle.