x^2+15x+72=0

Solution for x^2+15x+72=0 equation:

Simplifying
x2 + 15x + 72 = 0

Reorder the terms:
72 + 15x + x2 = 0

Solving
72 + 15x + x2 = 0

Solving for variable 'x'.

Begin completing the square.

Move the constant term to the right:

Add '-72' to each side of the equation.
72 + 15x + -72 + x2 = 0 + -72

Reorder the terms:
72 + -72 + 15x + x2 = 0 + -72

Combine like terms: 72 + -72 = 0
0 + 15x + x2 = 0 + -72
15x + x2 = 0 + -72

Combine like terms: 0 + -72 = -72
15x + x2 = -72

The x term is 15x.  Take half its coefficient (7.5).
Square it (56.25) and add it to both sides.

Add '56.25' to each side of the equation.
15x + 56.25 + x2 = -72 + 56.25

Reorder the terms:
56.25 + 15x + x2 = -72 + 56.25

Combine like terms: -72 + 56.25 = -15.75
56.25 + 15x + x2 = -15.75

Factor a perfect square on the left side:
(x + 7.5)(x + 7.5) = -15.75

Can't calculate square root of the right side.

The solution to this equation could not be determined.