(-5v^2+8v+5)+(3v^2-8v-6)-(4v^2-9v-9)=

Solution for (-5v^2+8v+5)+(3v^2-8v-6)-(4v^2-9v-9)= equation:

Simplifying
(-5v2 + 8v + 5) + (3v2 + -8v + -6) + -1(4v2 + -9v + -9) = 0

Reorder the terms:
(5 + 8v + -5v2) + (3v2 + -8v + -6) + -1(4v2 + -9v + -9) = 0

Remove parenthesis around (5 + 8v + -5v2)
5 + 8v + -5v2 + (3v2 + -8v + -6) + -1(4v2 + -9v + -9) = 0

Reorder the terms:
5 + 8v + -5v2 + (-6 + -8v + 3v2) + -1(4v2 + -9v + -9) = 0

Remove parenthesis around (-6 + -8v + 3v2)
5 + 8v + -5v2 + -6 + -8v + 3v2 + -1(4v2 + -9v + -9) = 0

Reorder the terms:
5 + 8v + -5v2 + -6 + -8v + 3v2 + -1(-9 + -9v + 4v2) = 0
5 + 8v + -5v2 + -6 + -8v + 3v2 + (-9 * -1 + -9v * -1 + 4v2 * -1) = 0
5 + 8v + -5v2 + -6 + -8v + 3v2 + (9 + 9v + -4v2) = 0

Reorder the terms:
5 + -6 + 9 + 8v + -8v + 9v + -5v2 + 3v2 + -4v2 = 0

Combine like terms: 5 + -6 = -1
-1 + 9 + 8v + -8v + 9v + -5v2 + 3v2 + -4v2 = 0

Combine like terms: -1 + 9 = 8
8 + 8v + -8v + 9v + -5v2 + 3v2 + -4v2 = 0

Combine like terms: 8v + -8v = 0
8 + 0 + 9v + -5v2 + 3v2 + -4v2 = 0
8 + 9v + -5v2 + 3v2 + -4v2 = 0

Combine like terms: -5v2 + 3v2 = -2v2
8 + 9v + -2v2 + -4v2 = 0

Combine like terms: -2v2 + -4v2 = -6v2
8 + 9v + -6v2 = 0

Solving
8 + 9v + -6v2 = 0

Solving for variable 'v'.

Begin completing the square.  Divide all terms by
-6 the coefficient of the squared term: 

Divide each side by '-6'.
-1.333333333 + -1.5v + v2 = 0

Move the constant term to the right:

Add '1.333333333' to each side of the equation.
-1.333333333 + -1.5v + 1.333333333 + v2 = 0 + 1.333333333

Reorder the terms:
-1.333333333 + 1.333333333 + -1.5v + v2 = 0 + 1.333333333

Combine like terms: -1.333333333 + 1.333333333 = 0.000000000
0.000000000 + -1.5v + v2 = 0 + 1.333333333
-1.5v + v2 = 0 + 1.333333333

Combine like terms: 0 + 1.333333333 = 1.333333333
-1.5v + v2 = 1.333333333

The v term is -1.5v.  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.
-1.5v + 0.5625 + v2 = 1.333333333 + 0.5625

Reorder the terms:
0.5625 + -1.5v + v2 = 1.333333333 + 0.5625

Combine like terms: 1.333333333 + 0.5625 = 1.895833333
0.5625 + -1.5v + v2 = 1.895833333

Factor a perfect square on the left side:
(v + -0.75)(v + -0.75) = 1.895833333

Calculate the square root of the right side: 1.376892637

Break this problem into two subproblems by setting 
(v + -0.75) equal to 1.376892637 and -1.376892637.

Subproblem 1
v + -0.75 = 1.376892637

Simplifying
v + -0.75 = 1.376892637

Reorder the terms:
-0.75 + v = 1.376892637

Solving
-0.75 + v = 1.376892637

Solving for variable 'v'.

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

Add '0.75' to each side of the equation.
-0.75 + 0.75 + v = 1.376892637 + 0.75

Combine like terms: -0.75 + 0.75 = 0.00
0.00 + v = 1.376892637 + 0.75
v = 1.376892637 + 0.75

Combine like terms: 1.376892637 + 0.75 = 2.126892637
v = 2.126892637

Simplifying
v = 2.126892637

Subproblem 2
v + -0.75 = -1.376892637

Simplifying
v + -0.75 = -1.376892637

Reorder the terms:
-0.75 + v = -1.376892637

Solving
-0.75 + v = -1.376892637

Solving for variable 'v'.

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

Add '0.75' to each side of the equation.
-0.75 + 0.75 + v = -1.376892637 + 0.75

Combine like terms: -0.75 + 0.75 = 0.00
0.00 + v = -1.376892637 + 0.75
v = -1.376892637 + 0.75

Combine like terms: -1.376892637 + 0.75 = -0.626892637
v = -0.626892637

Simplifying
v = -0.626892637

Solution
The solution to the problem is based on the solutions
from the subproblems.
v = {2.126892637, -0.626892637}