Respuesta :

The value of y in the cyclic quadrilateral with ∠AOC(142°) is 38°

The diagram above represents a cyclic quadrilateral.

A cyclic quadrilateral has all it vertices on the circumference of the circle.

Therefore,

Opposite angles are supplementary. This means they add up to 180 degrees.

Therefore,

142° + y° = 180°

subtract 142 from both sides of the equation

142 - 142 + y = 180 - 142

y = 38°

learn more about circle theorem here: https://brainly.com/question/24795394