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                In a quadrilateral ABCD, angle A = 
				angle D = 60 degrees, AC = BD, AB = a, AD = 3a, and the length 
				of CD is greater than the length of AB. AC and BD intersect at 
				E. Prove that
				(1) ; 
				(2) AE = 3BE; (3) BC is perpendicular to CD; (4)  ; 
				(5)  . 
				(Trigonometry is not allowed.) This entry contributed by Sumith Peiris, Moratuwa, Sri Lanka.
 
 
		 
 
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