2010 · Q54
In the figure given above (cyclic quadrilateral ABCD with secants P-D-A and P-C-B meeting at external point P), if ∠BAD = 60°, ∠ADC = 105°, then what is ∠DPC equal to ?
Elementary MathematicsGeometry
- A40°
- B45°
- C50°
- D60°
Explanation
Cyclic quadrilateral: arc BD=120°, arc ABC=210°; ∠DPC=½(arc AB-arc DC)=45°.