2x^2+k+1=0

Solution for 2x^2+k+1=0 equation:

Simplifying
2x2 + k + 1 = 0

Reorder the terms:
1 + k + 2x2 = 0

Solving
1 + k + 2x2 = 0

Solving for variable 'k'.

Move all terms containing k to the left, all other terms to the right.

Add '-1' to each side of the equation.
1 + k + -1 + 2x2 = 0 + -1

Reorder the terms:
1 + -1 + k + 2x2 = 0 + -1

Combine like terms: 1 + -1 = 0
0 + k + 2x2 = 0 + -1
k + 2x2 = 0 + -1

Combine like terms: 0 + -1 = -1
k + 2x2 = -1

Add '-2x2' to each side of the equation.
k + 2x2 + -2x2 = -1 + -2x2

Combine like terms: 2x2 + -2x2 = 0
k + 0 = -1 + -2x2
k = -1 + -2x2

Simplifying
k = -1 + -2x2