If A is the center of the circle shown above and AB = BC = CD, what is
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29 Nov 2021, 07:50
Consider \(\triangle ABC\)
We are given that \(AB = BC = CD\)
We can infer from the diagram that \(AB\) and \(AC\) are both radii of the circles
So, now we have \(AB = AC = r\) also \(AB = BC\)
Hence, we can easily say that \(AB = BC = AC\), which makes \(\triangle ABC\) an equilateral triangle
Using property - All angles in a equilateral triangle are equal to 60 degrees
Similar case goes for \(\triangle ADC\) which essentially makes \(BD\) an median and angle bisector at \(B\) as well as at \(D\)
Therefore, \(x^o = \frac{∠ABC}{2} = \frac{60^o}{2} = 30^o\)
Hence, Answer is B