2.5x^2+10x+15=0

Solution for 2.5x^2+10x+15=0 equation:

Simplifying
2.5x2 + 10x + 15 = 0

Reorder the terms:
15 + 10x + 2.5x2 = 0

Solving
15 + 10x + 2.5x2 = 0

Solving for variable 'x'.

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

Divide each side by '2.5'.
6 + 4x + x2 = 0

Move the constant term to the right:

Add '-6' to each side of the equation.
6 + 4x + -6 + x2 = 0 + -6

Reorder the terms:
6 + -6 + 4x + x2 = 0 + -6

Combine like terms: 6 + -6 = 0
0 + 4x + x2 = 0 + -6
4x + x2 = 0 + -6

Combine like terms: 0 + -6 = -6
4x + x2 = -6

The x term is 4x.  Take half its coefficient (2).
Square it (4) and add it to both sides.

Add '4' to each side of the equation.
4x + 4 + x2 = -6 + 4

Reorder the terms:
4 + 4x + x2 = -6 + 4

Combine like terms: -6 + 4 = -2
4 + 4x + x2 = -2

Factor a perfect square on the left side:
(x + 2)(x + 2) = -2

Can't calculate square root of the right side.

The solution to this equation could not be determined.