IF L is the circumcentre of $$\triangle$$XYZ and angle X is $$40^\circ$$, then the value of $$\angle$$YZL is:
Given, L is the circumcentre of $$\triangle$$XYZ and $$\angle$$YXZ = $$40^\circ$$
Angle subtended by an arc of the circle at centre is twice the angle subtended by the arc at any point on the circle.
$$\Rightarrow$$ Angle subtended by the arc YZ at L is twice the angle subtended by the arc YZ at X.
$$\Rightarrow$$ $$\angle$$YLZ = 2$$\angle$$YXZ
$$\Rightarrow$$Â $$\angle$$YLZ =Â $$80^\circ$$
In $$\triangle$$LYZ, YL = ZL
Angles opposite to equal sides are equal.
$$\Rightarrow$$Â $$\angle$$YZL =Â $$\angle$$ZYL
Also, $$\angle$$YZL + $$\angle$$ZYL + $$\angle$$YLZ = $$180^\circ$$
$$\Rightarrow$$Â $$\angle$$YZL +Â $$\angle$$YZL +Â $$80^\circ$$ =Â $$180^\circ$$
$$\Rightarrow$$ 2$$\angle$$YZL =Â $$100^\circ$$
$$\Rightarrow$$Â $$\angle$$YZL =Â $$50^\circ$$
Hence, the correct answer is Option A
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