# AB and CD are two equal chords of a circle with centre O such that ∠AOB = 80°, then ∠COD = ?

Question:

AB and CD are two equal chords of a circle with centre O such that AOB = 80°, then ∠COD = ?
(a) 100°
(b) 80°
(c) 120°
(d) 40°

Solution:

(b) 80°
Given: AB = CD
We know that equal chords of a circle subtend equal angles at the centre.
∴ ∠COD = ∠AOB = 80°
The passage contains a geometric problem involving equal chords of a circle and the angles they subtend at the center, followed by a multiple-choice question and its solution.
single_question_with_answer
Given a text passage, determine:
    1. If it contains a mathematical question (including word problems or calculations)
    2. If an answer to that mathematical question is provided in the text

First, describe the content structure you found in 1-2 sentences.

Then provide your analysis in the following format:
TYPE: <one of the following values>
- NO_QUESTION
- SINGLE_QUESTION
- SINGLE_QUESTION_WITH_ANSWER
- MULTIPLE_QUESTIONS
- MULTIPLE_QUESTIONS_WITH_ANSWERS
system
# AB and CD are two equal chords of a circle with centre O such that ∠AOB = 80°, then ∠COD = ?

Question:

AB and CD are two equal chords of a circle with centre O such that AOB = 80°, then ∠COD = ?
(a) 100°
(b) 80°
(c) 120°
(d) 40°

Solution:

(b) 80°
Given: AB = CD
We know that equal chords of a circle subtend equal angles at the centre.
∴ ∠COD = ∠AOB = 80°
user
The passage contains a geometric problem involving equal chords of a circle and the angles they subtend at the center, followed by a multiple-choice question and its solution.

TYPE: SINGLE_QUESTION_WITH_ANSWER