A cyclic quadrilateral is a quadrilateral with all four vertices or corners lying on the circumference of a circle.
Properties
- The opposite angles add up to 180°(supplementary angles)
(abbreviated to opp. s of cyclic quad are supp.)
a + c = 180o
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- The exterior angle of a cyclic quadrilateral is equal to the interior opposite angle.
(abbreviated to ext. of cyclic quad = int.opp. )
e = f
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Find the value of the angles and give reasons. |
x = 180° − 121° ( opp. s of cyclic quad are supp.) z = 75° ( ext. of cyclic quad = int.opp. )
y = 180° − 75° (adj. s on st. line are supp.)
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