7x^2+4x-128=0

Solution for 7x^2+4x-128=0 equation:

Simplifying
7x2 + 4x + -128 = 0

Reorder the terms:
-128 + 4x + 7x2 = 0

Solving
-128 + 4x + 7x2 = 0

Solving for variable 'x'.

Factor a trinomial.
(-32 + -7x)(4 + -1x) = 0

Subproblem 1
Set the factor '(-32 + -7x)' equal to zero and attempt to solve:

Simplifying
-32 + -7x = 0

Solving
-32 + -7x = 0

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

Add '32' to each side of the equation.
-32 + 32 + -7x = 0 + 32

Combine like terms: -32 + 32 = 0
0 + -7x = 0 + 32
-7x = 0 + 32

Combine like terms: 0 + 32 = 32
-7x = 32

Divide each side by '-7'.
x = -4.571428571

Simplifying
x = -4.571428571
Subproblem 2
Set the factor '(4 + -1x)' equal to zero and attempt to solve:

Simplifying
4 + -1x = 0

Solving
4 + -1x = 0

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

Add '-4' to each side of the equation.
4 + -4 + -1x = 0 + -4

Combine like terms: 4 + -4 = 0
0 + -1x = 0 + -4
-1x = 0 + -4

Combine like terms: 0 + -4 = -4
-1x = -4

Divide each side by '-1'.
x = 4

Simplifying
x = 4
Solution
x = {-4.571428571, 4}