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(n (n + 1))/2 = 55 then n = …...

`(n (n + 1))/2 = 55` then n = …

A

13

B

16

C

10

D

12

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BEYOND PUBLICATION-QUADRATIC EQUATIONS-EXAMPLE
  1. (n (n + 1))/2 = 55 then n = …

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  2. Check whether the following are quadratic equations: (x - 2)^(2) + 1...

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  3. Check whether the following are quadratic equation: x(x+1)+8=(x+2)(x...

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  4. Check whether the following are quadratic equation: x(2x+3)=x^(2)+1

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  5. Check whether the following are quadratic equation: (x+2)^(3)=x^(3)-4

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  6. Check whether the following are quadratic equations: (x + 1)^(2) = 2...

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  7. Chek whether the following are quadratic equation: x^(2)-2x=(-2)(3-x...

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  8. Chek whether the following are quadratic equation: (x-2)(x+1)=(x-1)...

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  9. Check whether the following are quadratic equations: (x - 3)(2x + 1)...

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  10. Chek whether the following are quadratic equation: (2x-1)(x-3)=(x+5)...

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  11. Chek whether the following are quadratic equation: x^(2)+3x+1=(x-2)^...

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  12. Chek whether the following are quadratic equation: (x+2)^(3)=2x(x^(2...

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  13. Chek whether the following are quadratic equation: x^(3)-4x^(2)-x+1=...

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  14. Represent the following situations in the form of quadratic equation: ...

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  15. Represent the following situations in the form of quadratic equation: ...

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  16. Represent the following situations in the form of quadratic equation: ...

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  17. A train travels a distance of 480 km at a uniform speed. If the speed ...

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  18. Verify that 1 and 3/2 are the roots of the equation 2x^(2) - 5x + 3 = ...

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  19. Find the roots of the equation 2x^(2) - 5x + 3 = 0 by factorisation.

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  20. Find the roots of the quadratic equation x - 1/(3x) = 1/6

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  21. Find the roots of the following quadratic equations by factorisation. ...

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