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gcse last minute circle theorem help?

ignore this sorted now
(edited 6 years ago)
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Very Last minute!
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ignore this sorted now
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Original post by lostplot
Very Last minute!


let the centre be O.

Join BO and CO.

Angle OBQ = 90.

Angle OBC = Angle BCO = 90 - x, because BOC is an isosceles triangle

Hence, because OBC is triangle,
angle BOC = 180 - (Angle OBC+ Angle BCO) = 2x.

So, angle CAB = x, using angle of segment is half of angle of the same segment on the centre of circle.

So, angle CAB = angle CBA = x (because BC is bisector of angle ABQ).

So, AC = BC (converse of isosceles triangle).

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