Question

Given: quadrilateral ABCD inscribed in a circle Prove: ∠A and ∠C are supplementary, ∠B and ∠D are supplementary

What is the missing information in the paragraph proof?

Answer 1

Answer: inscribed angle

Explanation:

Right on edg

Answer 2

Explanation:

Given that quadrilateral ABCD inscribed in a circle

We have angle A and C are lying on either side of the centre.

If O is the centre, we get

AOC will be 2A (as per subtended arc theorem)

Similarly AOC major arc would be 2C

Since 2A+2C = 360(angle around a point)

dividing by 2, we get A+C =180

Or A and C are supplementary

Similarly we can prove B and D are supplementary.