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Question
In the figure, a circle with center C has m(arc AXB) = 100° then find central ∠ACB and measure m(arc AYB).
Solution
In the given figure, m(arc AXB) = ∠ACB ......[Definition of measure of minor arc]
∴ ∠ACB = 100°
m(arc AXB) + m(arc AYB) = 360° ......[Measure of complete circle is 360°]
∴ 100° + m(arc AYB) = 360°
∴ m(arc AYB) = 360° – 100°
∴ m(arc AYB) = 260°
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