In the figure given below, smaller circle touches bigger circle at point C. A is the center of bigger circle while B is the center of smaller circle. ∠ABE = 45°. If BC = 3 cm, find DE
Explanation:
Let us draw EP perpendicular to AB and join EA.
Let AP = x
In ∆BEP, ∠EBP = ∠BEP = 45° ∴ BP = EP = 3 + x
In ∆AEP ⇒ AE2 = AP2 + PE2 ⇒ 62 = (x)2 + (3 + x)2 ⇒ 36 = x2 + 9 + x2 + 6x ⇒ 2x2 + 6x - 27 = 0 ⇒ x = -6+674 = 37-32
⇒ EB = √2(3 + x) = 23+37-32 = 37+32
⇒ ED = EB - DB = 37+32 - 3 = 37-32+32
Hence, option (b).
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