21x^2-11x+9=0

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Solution for 21x^2-11x+9=0 equation:


Simplifying
21x2 + -11x + 9 = 0

Reorder the terms:
9 + -11x + 21x2 = 0

Solving
9 + -11x + 21x2 = 0

Solving for variable 'x'.

Begin completing the square.  Divide all terms by
21 the coefficient of the squared term: 

Divide each side by '21'.
0.4285714286 + -0.5238095238x + x2 = 0

Move the constant term to the right:

Add '-0.4285714286' to each side of the equation.
0.4285714286 + -0.5238095238x + -0.4285714286 + x2 = 0 + -0.4285714286

Reorder the terms:
0.4285714286 + -0.4285714286 + -0.5238095238x + x2 = 0 + -0.4285714286

Combine like terms: 0.4285714286 + -0.4285714286 = 0.0000000000
0.0000000000 + -0.5238095238x + x2 = 0 + -0.4285714286
-0.5238095238x + x2 = 0 + -0.4285714286

Combine like terms: 0 + -0.4285714286 = -0.4285714286
-0.5238095238x + x2 = -0.4285714286

The x term is -0.5238095238x.  Take half its coefficient (-0.2619047619).
Square it (0.06859410431) and add it to both sides.

Add '0.06859410431' to each side of the equation.
-0.5238095238x + 0.06859410431 + x2 = -0.4285714286 + 0.06859410431

Reorder the terms:
0.06859410431 + -0.5238095238x + x2 = -0.4285714286 + 0.06859410431

Combine like terms: -0.4285714286 + 0.06859410431 = -0.35997732429
0.06859410431 + -0.5238095238x + x2 = -0.35997732429

Factor a perfect square on the left side:
(x + -0.2619047619)(x + -0.2619047619) = -0.35997732429

Can't calculate square root of the right side.

The solution to this equation could not be determined.

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