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Showing posts from August, 2022

### Mathematics Assignments | PDF | 8 to 12

PDF Files of Mathematics Assignments From VIII Standard to XII Standard PDF of mathematics Assignments for the students from VIII standard to XII standard.These assignments are strictly according to the CBSE and DAV Board Final question Papers

### Theorems on Quadrilaterals Ch-8 Class-IX

Theorems on Parallelograms Ch-8 Class-IX Explanation of all theorems on Parallelograms chapter 8 class IX, Theorem 8.1, 8.2, 8.3, 8.4, 8.5, 8.6, 8.7, 8.8, 8.9, 8.10, Mid point theorem and its converse. All theorems of chapter 8 class IX. Theorem 8.1: Prove that a diagonal of a parallelogram divides it into two congruent triangles. Given: In Parallelogram ABCD, AC is the diagonal To Prove:  △ACD ≌ △ABC Proof: In △ACD and △ABC,  ∠1 = ∠2  .........   (Alternate angles ∠3 = ∠4  ..........  (Alternate interior angles AC = AC ........   (Common Sides ⇒ By ASA  ≌ rule   △ACD ≌ △ABC   Theorem 8.2: In a parallelogram, opposite sides are equal. Given: ABCD is a parallelogram To Prove : AB = CD and BC = AD Proof:  In △ ACD and △ ABC,  ∠ 1 = ∠ 2  .........   (Alternate angles ∠ 3 = ∠ 4  ..........  (Alternate interior angles AC = AC ........   (Common Sides ⇒ By ASA  ≌ rule   △ ACD ≌ △ ABC ⇒ AB = CD and BC = AD  …..  By CPCT Theorem