In a circle of radius 11 cm, CD is a diameter and AB is a chord of length 20.5 cm. If AB and CD intersect at a point E inside the circle and CE has length 7 cm, then the difference of the lengths of BE and AE, in cm, is
In figure AE*BE=CE*DE  (The  intersecting chords theorem)
=> 7*15= x(20.5-x)Â Â Â Â Â Â Â Â Â (Assuming AE=x)
=> 210=x(41-2x)
=>Â $$2x^2$$-41x+210=0
=> x=10 or x=10.5Â Â => AE=10 or AE=10.5Â Â Â Hence BE = 20.5-10=10.5Â or BE = 20.5-10.5=10
Required difference= 10.5-10=0.5
CAT Averages, Ratios & Proportions
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