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Forums
Proof for a cyclic quadrilateral

Proof for a cyclic quadrilateral

Lasagneee

"Prove that the sum of the opposite angles of a cyclic quadrilateral add up to 180 degrees"

Not sure how to prove this in a simple way, can anyone help please?

Reply 1

Matureb

Draw a circle, with your cyclic quad inside. Call quad abcd and draw bOd where O is the centre of the circle.
What do you know about the angle bOd?

Reply 2

the bear

yep as the previous poster said.... draw a diagram. join the four points to the centre.

Quick Reply

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