Question

Find the value of the marked angles in each of the following ( see image ).

Please show workings.

The only given angle is 126°.

The angle to look for is marked by “))”​

Answer 1

• 117°

Explanation:

The central angle is twice the inscribed angle (same arc).

The inscribed angle forms a supplementary angle with the missing one (opposite angles of the cyclic quadrilateral).

The missing angle is:

• 180° - 1/2(126°) = 180° - 63° = 117°