Cyclic quadrilaterals
Plane geometry · Mathematics
Study notes
Q: Cyclic quadrilateral ABCD: ∠A = 70°, ∠B = 85°. Find ∠C, ∠D. ∠C = 180° - 70° = 110° (opposite A!). ∠D = 180° - 85° = 95° (opposite B!). Check: 70+110+85+95 = 360 ✓!
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Plane geometry · Mathematics
Q: Cyclic quadrilateral ABCD: ∠A = 70°, ∠B = 85°. Find ∠C, ∠D. ∠C = 180° - 70° = 110° (opposite A!). ∠D = 180° - 85° = 95° (opposite B!). Check: 70+110+85+95 = 360 ✓!