5x^2+9x+18=0

Solution for 5x^2+9x+18=0 equation:

Simplifying
5x2 + 9x + 18 = 0

Reorder the terms:
18 + 9x + 5x2 = 0

Solving
18 + 9x + 5x2 = 0

Solving for variable 'x'.

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

Divide each side by '5'.
3.6 + 1.8x + x2 = 0

Move the constant term to the right:

Add '-3.6' to each side of the equation.
3.6 + 1.8x + -3.6 + x2 = 0 + -3.6

Reorder the terms:
3.6 + -3.6 + 1.8x + x2 = 0 + -3.6

Combine like terms: 3.6 + -3.6 = 0.0
0.0 + 1.8x + x2 = 0 + -3.6
1.8x + x2 = 0 + -3.6

Combine like terms: 0 + -3.6 = -3.6
1.8x + x2 = -3.6

The x term is 1.8x.  Take half its coefficient (0.9).
Square it (0.81) and add it to both sides.

Add '0.81' to each side of the equation.
1.8x + 0.81 + x2 = -3.6 + 0.81

Reorder the terms:
0.81 + 1.8x + x2 = -3.6 + 0.81

Combine like terms: -3.6 + 0.81 = -2.79
0.81 + 1.8x + x2 = -2.79

Factor a perfect square on the left side:
(x + 0.9)(x + 0.9) = -2.79

Can't calculate square root of the right side.

The solution to this equation could not be determined.