3x^2-20x+31=0

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Solution for 3x^2-20x+31=0 equation:


Simplifying
3x2 + -20x + 31 = 0

Reorder the terms:
31 + -20x + 3x2 = 0

Solving
31 + -20x + 3x2 = 0

Solving for variable 'x'.

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

Divide each side by '3'.
10.33333333 + -6.666666667x + x2 = 0

Move the constant term to the right:

Add '-10.33333333' to each side of the equation.
10.33333333 + -6.666666667x + -10.33333333 + x2 = 0 + -10.33333333

Reorder the terms:
10.33333333 + -10.33333333 + -6.666666667x + x2 = 0 + -10.33333333

Combine like terms: 10.33333333 + -10.33333333 = 0.00000000
0.00000000 + -6.666666667x + x2 = 0 + -10.33333333
-6.666666667x + x2 = 0 + -10.33333333

Combine like terms: 0 + -10.33333333 = -10.33333333
-6.666666667x + x2 = -10.33333333

The x term is -6.666666667x.  Take half its coefficient (-3.333333334).
Square it (11.11111112) and add it to both sides.

Add '11.11111112' to each side of the equation.
-6.666666667x + 11.11111112 + x2 = -10.33333333 + 11.11111112

Reorder the terms:
11.11111112 + -6.666666667x + x2 = -10.33333333 + 11.11111112

Combine like terms: -10.33333333 + 11.11111112 = 0.77777779
11.11111112 + -6.666666667x + x2 = 0.77777779

Factor a perfect square on the left side:
(x + -3.333333334)(x + -3.333333334) = 0.77777779

Calculate the square root of the right side: 0.881917111

Break this problem into two subproblems by setting 
(x + -3.333333334) equal to 0.881917111 and -0.881917111.

Subproblem 1

x + -3.333333334 = 0.881917111 Simplifying x + -3.333333334 = 0.881917111 Reorder the terms: -3.333333334 + x = 0.881917111 Solving -3.333333334 + x = 0.881917111 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '3.333333334' to each side of the equation. -3.333333334 + 3.333333334 + x = 0.881917111 + 3.333333334 Combine like terms: -3.333333334 + 3.333333334 = 0.000000000 0.000000000 + x = 0.881917111 + 3.333333334 x = 0.881917111 + 3.333333334 Combine like terms: 0.881917111 + 3.333333334 = 4.215250445 x = 4.215250445 Simplifying x = 4.215250445

Subproblem 2

x + -3.333333334 = -0.881917111 Simplifying x + -3.333333334 = -0.881917111 Reorder the terms: -3.333333334 + x = -0.881917111 Solving -3.333333334 + x = -0.881917111 Solving for variable 'x'. Move all terms containing x to the left, all other terms to the right. Add '3.333333334' to each side of the equation. -3.333333334 + 3.333333334 + x = -0.881917111 + 3.333333334 Combine like terms: -3.333333334 + 3.333333334 = 0.000000000 0.000000000 + x = -0.881917111 + 3.333333334 x = -0.881917111 + 3.333333334 Combine like terms: -0.881917111 + 3.333333334 = 2.451416223 x = 2.451416223 Simplifying x = 2.451416223

Solution

The solution to the problem is based on the solutions from the subproblems. x = {4.215250445, 2.451416223}

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