21x^2+17x+7=0

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Solution for 21x^2+17x+7=0 equation:


Simplifying
21x2 + 17x + 7 = 0

Reorder the terms:
7 + 17x + 21x2 = 0

Solving
7 + 17x + 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'.
0.3333333333 + 0.8095238095x + x2 = 0

Move the constant term to the right:

Add '-0.3333333333' to each side of the equation.
0.3333333333 + 0.8095238095x + -0.3333333333 + x2 = 0 + -0.3333333333

Reorder the terms:
0.3333333333 + -0.3333333333 + 0.8095238095x + x2 = 0 + -0.3333333333

Combine like terms: 0.3333333333 + -0.3333333333 = 0.0000000000
0.0000000000 + 0.8095238095x + x2 = 0 + -0.3333333333
0.8095238095x + x2 = 0 + -0.3333333333

Combine like terms: 0 + -0.3333333333 = -0.3333333333
0.8095238095x + x2 = -0.3333333333

The x term is 0.8095238095x.  Take half its coefficient (0.4047619048).
Square it (0.1638321996) and add it to both sides.

Add '0.1638321996' to each side of the equation.
0.8095238095x + 0.1638321996 + x2 = -0.3333333333 + 0.1638321996

Reorder the terms:
0.1638321996 + 0.8095238095x + x2 = -0.3333333333 + 0.1638321996

Combine like terms: -0.3333333333 + 0.1638321996 = -0.1695011337
0.1638321996 + 0.8095238095x + x2 = -0.1695011337

Factor a perfect square on the left side:
(x + 0.4047619048)(x + 0.4047619048) = -0.1695011337

Can't calculate square root of the right side.

The solution to this equation could not be determined.

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