x^2+40x-84=0

Solution for x^2+40x-84=0 equation:

Simplifying
x2 + 40x + -84 = 0

Reorder the terms:
-84 + 40x + x2 = 0

Solving
-84 + 40x + x2 = 0

Solving for variable 'x'.

Factor a trinomial.
(-42 + -1x)(2 + -1x) = 0

Subproblem 1
Set the factor '(-42 + -1x)' equal to zero and attempt to solve:

Simplifying
-42 + -1x = 0

Solving
-42 + -1x = 0

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

Add '42' to each side of the equation.
-42 + 42 + -1x = 0 + 42

Combine like terms: -42 + 42 = 0
0 + -1x = 0 + 42
-1x = 0 + 42

Combine like terms: 0 + 42 = 42
-1x = 42

Divide each side by '-1'.
x = -42

Simplifying
x = -42
Subproblem 2
Set the factor '(2 + -1x)' equal to zero and attempt to solve:

Simplifying
2 + -1x = 0

Solving
2 + -1x = 0

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

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

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

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

Divide each side by '-1'.
x = 2

Simplifying
x = 2
Solution
x = {-42, 2}