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The area of a circle is given by the exp...

The area of a circle is given by the expression `pi x ^(2) + 6pi x + 9pi.` Find the radius of the circle.

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NCERT EXEMPLAR-ALGEBRAIC EXPRESSIONS, IDENTITIES AND FACTORISATION -EXERCISE
  1. The area of a rectangle is x ^(2) + 7x + 12 . If its breadth is (x +...

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  2. The curved surface area of a cylinder is 2pi (y ^(2) - 7y + 12) and it...

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  3. The area of a circle is given by the expression pi x ^(2) + 6pi x + 9p...

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  4. The sum of first n natural numbers is given by the expression ( n ^(2)...

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  5. The sum of (x + 5) observations is x ^(4) - 625. Find the mean of the ...

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  6. The height of a triangle is x ^(4) + y ^(4) and its base is 14xy. Find...

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  7. The cost of a chocolate is Rs (x + y) and Rohit bought (x + y) chocola...

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  8. The base of a parallelogram is (2x + 3) units and the corresponding he...

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  9. The radius of a circle is 7ab – 7bc – 14ac. Find the circumference of ...

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  10. If p + q=12 and pq= 22, then find p^(2) + q ^(2).

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  11. If a+b=25 and a^(2)+b^(2)=225 then find ab

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  12. If x -y = 13 and xy = 28, then find x ^(2) + y ^(2).

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  13. If m -n = 16 and m ^(2) + n ^(2) = 400, then find mn.

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  14. If a ^(2) + b ^(2) = 74 and ab = 35, then find a + b.

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  15. Verify that (ab+ bc) (ab- bc) + (bc+ ca) (bc- ca) + (ca + ab) (ca- a...

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  16. Verify that (a +b + c) (a ^(2) + b ^(2) + c ^(2) - ab - bc - ca) = a...

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  17. Verify that (p-q) ( p ^(2) + pq + q ^(2)) = p ^(3) - q ^(3)

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  18. Verify that (m + n) ( m ^(2) - mn + n ^(2)) = m ^(3) + n ^(3)

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  19. Verify the (a+b ) (a+b) (a +b) = a ^(3) + 3a ^(2) b + 3a^(2) b + 3a ...

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  20. Verify that (a-b) (a -b) (a-b) = a ^(3) - 3a ^(2) b + 3a b ^(2) - b ...

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