A sector of a circle ABO has a radius "r" and a central angle of 45° at 0, the center of the circle, with AB as the arc. A line is drawn from point A to point X, where X is the midpoint of OB. If the...

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Extracted text: A sector of a circle ABO has a radius "r" and a central angle of 45° at 0, the center of the circle, with AB as the arc. A line is drawn from point A to point X, where X is the midpoint of OB. If the area of section ABX is 4.5 cm?, compute the radius of the circle, " r ". Select one: a. 3.84 cm O b. 4 cm O c. 3 cm d. 4.57 cm v