This is the basic and conceptual question from Chapter name- circles
Topic – Angle properties of circles
Chapter number- 15
In the figure (i) ABCD is a quadrilateral inscribed in a circle with centre O. CD is produced to E. ∠ADE = 70° and ∠OBA = 45°, then we have to calculate (i) ∠OCA (ii) ∠BAC
In figure (ii) given below, ABF is a straight line and BE || DC.
∠DAB = 92° and ∠EBF = 20°, now we have to find : (i) ∠BCD (ii) ∠ADC.
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Understanding ICSE Mathematics