x^2-4x-316=209

Solution for x^2-4x-316=209 equation:

Simplifying
x2 + -4x + -316 = 209

Reorder the terms:
-316 + -4x + x2 = 209

Solving
-316 + -4x + x2 = 209

Solving for variable 'x'.

Reorder the terms:
-316 + -209 + -4x + x2 = 209 + -209

Combine like terms: -316 + -209 = -525
-525 + -4x + x2 = 209 + -209

Combine like terms: 209 + -209 = 0
-525 + -4x + x2 = 0

Factor a trinomial.
(-21 + -1x)(25 + -1x) = 0

Subproblem 1
Set the factor '(-21 + -1x)' equal to zero and attempt to solve:

Simplifying
-21 + -1x = 0

Solving
-21 + -1x = 0

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

Add '21' to each side of the equation.
-21 + 21 + -1x = 0 + 21

Combine like terms: -21 + 21 = 0
0 + -1x = 0 + 21
-1x = 0 + 21

Combine like terms: 0 + 21 = 21
-1x = 21

Divide each side by '-1'.
x = -21

Simplifying
x = -21
Subproblem 2
Set the factor '(25 + -1x)' equal to zero and attempt to solve:

Simplifying
25 + -1x = 0

Solving
25 + -1x = 0

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

Add '-25' to each side of the equation.
25 + -25 + -1x = 0 + -25

Combine like terms: 25 + -25 = 0
0 + -1x = 0 + -25
-1x = 0 + -25

Combine like terms: 0 + -25 = -25
-1x = -25

Divide each side by '-1'.
x = 25

Simplifying
x = 25
Solution
x = {-21, 25}