x^2+x=9900

Solution for x^2+x=9900 equation:

Simplifying
x2 + x = 9900

Reorder the terms:
x + x2 = 9900

Solving
x + x2 = 9900

Solving for variable 'x'.

Reorder the terms:
-9900 + x + x2 = 9900 + -9900

Combine like terms: 9900 + -9900 = 0
-9900 + x + x2 = 0

Factor a trinomial.
(-100 + -1x)(99 + -1x) = 0

Subproblem 1
Set the factor '(-100 + -1x)' equal to zero and attempt to solve:

Simplifying
-100 + -1x = 0

Solving
-100 + -1x = 0

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

Add '100' to each side of the equation.
-100 + 100 + -1x = 0 + 100

Combine like terms: -100 + 100 = 0
0 + -1x = 0 + 100
-1x = 0 + 100

Combine like terms: 0 + 100 = 100
-1x = 100

Divide each side by '-1'.
x = -100

Simplifying
x = -100
Subproblem 2
Set the factor '(99 + -1x)' equal to zero and attempt to solve:

Simplifying
99 + -1x = 0

Solving
99 + -1x = 0

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

Add '-99' to each side of the equation.
99 + -99 + -1x = 0 + -99

Combine like terms: 99 + -99 = 0
0 + -1x = 0 + -99
-1x = 0 + -99

Combine like terms: 0 + -99 = -99
-1x = -99

Divide each side by '-1'.
x = 99

Simplifying
x = 99
Solution
x = {-100, 99}