(2x+1)(x+1)=-1

Solution for (2x+1)(x+1)=-1 equation:

Simplifying
(2x + 1)(x + 1) = -1

Reorder the terms:
(1 + 2x)(x + 1) = -1

Reorder the terms:
(1 + 2x)(1 + x) = -1

Multiply (1 + 2x) * (1 + x)
(1(1 + x) + 2x * (1 + x)) = -1
((1 * 1 + x * 1) + 2x * (1 + x)) = -1
((1 + 1x) + 2x * (1 + x)) = -1
(1 + 1x + (1 * 2x + x * 2x)) = -1
(1 + 1x + (2x + 2x2)) = -1

Combine like terms: 1x + 2x = 3x
(1 + 3x + 2x2) = -1

Solving
1 + 3x + 2x2 = -1

Solving for variable 'x'.

Reorder the terms:
1 + 1 + 3x + 2x2 = -1 + 1

Combine like terms: 1 + 1 = 2
2 + 3x + 2x2 = -1 + 1

Combine like terms: -1 + 1 = 0
2 + 3x + 2x2 = 0

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

Divide each side by '2'.
1 + 1.5x + x2 = 0

Move the constant term to the right:

Add '-1' to each side of the equation.
1 + 1.5x + -1 + x2 = 0 + -1

Reorder the terms:
1 + -1 + 1.5x + x2 = 0 + -1

Combine like terms: 1 + -1 = 0
0 + 1.5x + x2 = 0 + -1
1.5x + x2 = 0 + -1

Combine like terms: 0 + -1 = -1
1.5x + x2 = -1

The x term is 1.5x.  Take half its coefficient (0.75).
Square it (0.5625) and add it to both sides.

Add '0.5625' to each side of the equation.
1.5x + 0.5625 + x2 = -1 + 0.5625

Reorder the terms:
0.5625 + 1.5x + x2 = -1 + 0.5625

Combine like terms: -1 + 0.5625 = -0.4375
0.5625 + 1.5x + x2 = -0.4375

Factor a perfect square on the left side:
(x + 0.75)(x + 0.75) = -0.4375

Can't calculate square root of the right side.

The solution to this equation could not be determined.