Folding A onto B creates the perpendicular bisector crease across AB, marking its midpoint. Since this crease is parallel to side BC, by the Converse of the Midpoint Theorem it also bisects AC.
Class 9 Ganita Manjari part 2 Chapter 12 Solutions
Class 9 Ganita Manjari Part 2 Chapter 12 Page 76 Question Answer
Folding point A onto point B makes the fold crease the perpendicular bisector of segment AB, directly marking the midpoint of AB. Because ∠B = 90° and the crease is perpendicular to AB, the crease line is parallel to base BC. By the Converse of the Midpoint Theorem, this line drawn through the midpoint of AB parallel to BC bisects side AC.
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