cooperroman wrote:
Why can we assume that AB is the diameter? In theory, couldn't Angle AOB be something other than 90 degrees and we need statement 2 to guarantee that AB is the diameter?
I think you meant 180 degrees instead of 90 degrees. Anyway, check the highlighted parts below:
Problem SolvingFigures: All figures accompanying problem solving questions are intended to provide information useful in solving the problems. Figures are drawn as accurately as possible. Exceptions will be clearly noted.
Lines shown as straight are straight, and lines that appear jagged are also straight. The positions of points, angles, regions, etc., exist in the order shown, and angle measures are greater than zero. All figures lie in a plane unless otherwise indicated.
Data Sufficiency:Figures:• Figures conform to the information given in the question, but will not necessarily conform to the additional information given in statements (1) and (2).
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Lines shown as straight are straight, and lines that appear jagged are also straight.
• The positions of points, angles, regions, etc., exist in the order shown, and angle measures are greater than zero.
• All figures lie in a plane unless otherwise indicated.
Hope it helps.
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