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Show that if the diagonal of a quadrilateral bisect each other at right angle,then it is a rhombus |
Answer» Answer:-Let ABCD be a quadrilateral whose diagonals bisect each other at right ANGLES. ★ GIVEN that:- OA = OC OB = OD ∠AOB = ∠BOC = ∠OCD = ∠ODA = 90° ★ To show that:- If the diagonals of a quadrilateral bisect each other at right angles, then it is a rhombus. ★ To PROVE that:- ABCD is parallelogram and AB = BC = CD = AD ★ Proof, In ΔAOB and ΔCOB, OA = OC (Given) ∠AOB = ∠COB (Opposite sides of a parallelogram are equal) OB = OB (Common) Therefore, ΔAOB ≅ ΔCOB [SAS congruency] Thus, AB = BC [CPCT] ★ Similarly we can prove, BC = CD CD = AD AD = AB AB = BC = CD = AD Opposites sides of a quadrilateral are equal hence ABCD is a parallelogram. ABCD is rhombus as it is a parallelogram whose diagonals intersect at right angle. Hence Proved. |
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