Adjacent angles of a parallelogram sum to 180°, so their bisectors add to 90°, forcing right angles at intersections to form a rectangle. If AB = BC, all bisectors intersect at a single point.
Cbse Class 9 Maths Ganita Manjari Part 2 Solutions
class 9 maths ganita manjari part 2 chapter 12 question answer
Adjacent angles of parallelogram ABCD are supplementary, summing to 180°. In triangles formed by adjacent bisectors, half-angles sum to 90°, forcing each intersection angle to be 90°. As all four interior angles equal 90°, the figure PQRS is a rectangle. We assume AB ≠ BC because if AB = BC (a rhombus), the angle bisectors are the diagonals, which concur at one point rather than forming a quadrilateral.
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