Question

Prove that, any Rectangle is a cyclic quadrilateral.​

Answer 1

ABCD be a cyclic quadrilateral such that its diagonals AC and BD are the diameters of the circle through the vertices A, B, C, and D.

<ABC = 90° and < ADC = 90°

Similarly, BD is a diameter.

<DAB = 900 and <BCD = 90°

Therefore, < ABC = <ADC = <DAB = <BCD = 90°

Thus, ABCD is a rectangle

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