Question

Points A and B are the endpoints of an arc of a circle. Chords are drawn from the two endpoints to a third point, C, on the circle.

Given and ,
° and
°.

Answer 1

146°

Explanation:

Points A and B are the endpoints of an arc of a circle. Chords are drawn from the two endpoints to a third point, C, on the circle. Given m arch AB=64° and ⦣ABC=73°, m ⦣ABC=__ ° and m arch AC=__ °.

Solution:

Given that:

arc AB = 64° and ⦣ABC=73°

The Central Angle Theorem states that the central angle from two chosen points A and B on the circle is always twice the inscribed angle from those two points. The inscribed angle is any point along the outer arc AB and the two points A and B.

Therefore arc AC is the central angle of ⦣ABC. Using the central angle theorem gives:

arc AC = 2 * ⦣ABC

substituting:

arc AC = 2 * 73

arc AC = 146°