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X = DH = 4.859693179

BC = 1 ⇒ X = AFB = 72

Orange Area = 28

Simplified

Proof that X = 45°

Pink Area = 0.471404520791

Orange Area = 18

Proof that X = EHF = 45°

BAC + BEC = 120

Rectangle = 15.4919333848

X = CD = 10

Another Approach