The quadrilateral ABCD is inscribed in a circle. The ABC angle is 136 °, the CAD angle is 82 °. Find the angle ABD.

The inscribed angle CAD = 82 and rests on the arc CD, then the degree measure of the arc CD = 2 * 82 = 164.

The inscribed angle ABC = 130 and rests on the arc ADC, then the degree measure of the arc ADC = 2 * 136 = 272.

Then the degree measure of the arc АD = ᵕADС – ᵕСD = 272 – 164 = 108.

The inscribed angle ABD rests on the arc AD and is equal to half of its degree measure. Angle ABD = 108/2 = 54.

Answer: The value of the angle ABD is 54.



One of the components of a person's success in our time is receiving modern high-quality education, mastering the knowledge, skills and abilities necessary for life in society. A person today needs to study almost all his life, mastering everything new and new, acquiring the necessary professional qualities.