3x^2+15x+40=0

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Solution for 3x^2+15x+40=0 equation:


Simplifying
3x2 + 15x + 40 = 0

Reorder the terms:
40 + 15x + 3x2 = 0

Solving
40 + 15x + 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'.
13.33333333 + 5x + x2 = 0

Move the constant term to the right:

Add '-13.33333333' to each side of the equation.
13.33333333 + 5x + -13.33333333 + x2 = 0 + -13.33333333

Reorder the terms:
13.33333333 + -13.33333333 + 5x + x2 = 0 + -13.33333333

Combine like terms: 13.33333333 + -13.33333333 = 0.00000000
0.00000000 + 5x + x2 = 0 + -13.33333333
5x + x2 = 0 + -13.33333333

Combine like terms: 0 + -13.33333333 = -13.33333333
5x + x2 = -13.33333333

The x term is 5x.  Take half its coefficient (2.5).
Square it (6.25) and add it to both sides.

Add '6.25' to each side of the equation.
5x + 6.25 + x2 = -13.33333333 + 6.25

Reorder the terms:
6.25 + 5x + x2 = -13.33333333 + 6.25

Combine like terms: -13.33333333 + 6.25 = -7.08333333
6.25 + 5x + x2 = -7.08333333

Factor a perfect square on the left side:
(x + 2.5)(x + 2.5) = -7.08333333

Can't calculate square root of the right side.

The solution to this equation could not be determined.

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