circle theorems im halfway done | Revision Server | Page 1

sleek dirge Mar 19, 2023, 10:13 AM

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tiny fog Mar 19, 2023, 10:23 AM

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If angle EAB is twice the angle of BCD,
we can call EAB (2x) and BCD and angle x

that means BDE = (180-2x) degrees as opposite angles in a cyclic quadrilateral add up to 180 degrees
That means BDC = 180 - (180-2x) = 180 - 180 + 2x = (2x) degrees as angles on a straight line add up to 180 degrees
So now in the small triangle, DBC = 60, BDC = 2x and BCD = x

tiny fog Mar 19, 2023, 10:23 AM

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sleek dirge

does this make sense?

sleek dirge Mar 19, 2023, 10:24 AM

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I did this but idk if it’s correct

#circle theorems im halfway done