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Prove that the area of an equilateral tr...

Prove that the area of an equilateral triangle is equal to `(sqrt(3))/4a^2,` where `a` is the side of the triangle. GIVEN : An equilateral triangle `A B C` such that `A B=B C=C A=a`. TO PROVE : `a r(triangle A B C)=(sqrt(3))/4a^2`. CONSTRUCTION : Draw `A D_|_B C`.

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RD SHARMA ENGLISH-AREA OF PARALLELOGRAMS AND TRIANGLES-All Questions
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  2. If the medians of a triangle A B C intersect at G , show that a r( tr...

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  3. Prove that the area of an equilateral triangle is equal to (sqrt(3))...

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  4. In a parallelogram A B C D ,E ,F are any two points on the sides A B a...

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  5. The diagonals of a parallelogram A B C D intersect at Odot A line thro...

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  6. Show that the segment joining the mid-points of a pair of opposite s...

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  7. Diagonals A C and B D of a trapezium A B C D with A B || C D intersect...

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  8. In Figure, A B C D is a quadrilateral and B E || A C and also B E meet...

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  9. If a triangle and a parallelogram are on the same base and between the...

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  10. In Figure, A B C D E is a pentagon. A line through B parallel to A C m...

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  11. Prove that The area of a parallelogram is the product of its base and...

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  12. Prove that Parallelograms on the same base and between the same para...

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  13. Prove that A diagonal of a parallelogram divides it into two triangl...

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  14. If each diagonal of a quadrilateral separates it into two triangles...

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  15. The area of a triangle is half the product of any of its sides and t...

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  16. Triangles A B C and DBC are on the same base B C with A, D on opposite...

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  17. If the diagonals A C ,B D of a quadrilateral A B C D , intersect at O ...

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  18. If P is any point in the interior of a parallelogram A B C D , then pr...

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  19. The diagonals of quadrilateral A B C D ,A C and B D intersect in Odot ...

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  20. X Y is a line parallel to side B C of triangle A B C. BE ll AC and C...

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