(5x^2-2x-1)+(2x-8x^2+4)=

Solution for (5x^2-2x-1)+(2x-8x^2+4)= equation:

Simplifying
(5x2 + -2x + -1) + (2x + -8x2 + 4) = 0

Reorder the terms:
(-1 + -2x + 5x2) + (2x + -8x2 + 4) = 0

Remove parenthesis around (-1 + -2x + 5x2)
-1 + -2x + 5x2 + (2x + -8x2 + 4) = 0

Reorder the terms:
-1 + -2x + 5x2 + (4 + 2x + -8x2) = 0

Remove parenthesis around (4 + 2x + -8x2)
-1 + -2x + 5x2 + 4 + 2x + -8x2 = 0

Reorder the terms:
-1 + 4 + -2x + 2x + 5x2 + -8x2 = 0

Combine like terms: -1 + 4 = 3
3 + -2x + 2x + 5x2 + -8x2 = 0

Combine like terms: -2x + 2x = 0
3 + 0 + 5x2 + -8x2 = 0
3 + 5x2 + -8x2 = 0

Combine like terms: 5x2 + -8x2 = -3x2
3 + -3x2 = 0

Solving
3 + -3x2 = 0

Solving for variable 'x'.

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

Add '-3' to each side of the equation.
3 + -3 + -3x2 = 0 + -3

Combine like terms: 3 + -3 = 0
0 + -3x2 = 0 + -3
-3x2 = 0 + -3

Combine like terms: 0 + -3 = -3
-3x2 = -3

Divide each side by '-3'.
x2 = 1

Simplifying
x2 = 1

Take the square root of each side:
x = {-1, 1}