Question

If ABCD is a cyclic quadrilateral. What will be the value of $x$ (in degrees)?

• A. ${120}^{\circ }$
• B. ${90}^{\circ }$
• C. ${100}^{\circ }$
• D. None of these

Answer 1

The correct option is C

${100}^{\circ }$

The sum of opposite angles of the cyclic quadrilateral is ${180}^{\circ }$.

$\angle DAB+\angle DCB={180}^{\circ }$

${80}^{\circ }+x={180}^{\circ }$

$\Rightarrow x={100}^{\circ }$