21(x^2+x-2)=0

Solution for 21(x^2+x-2)=0 equation:

Simplifying
21(x2 + x + -2) = 0

Reorder the terms:
21(-2 + x + x2) = 0
(-2 * 21 + x * 21 + x2 * 21) = 0
(-42 + 21x + 21x2) = 0

Solving
-42 + 21x + 21x2 = 0

Solving for variable 'x'.

Factor out the Greatest Common Factor (GCF), '21'.
21(-2 + x + x2) = 0

Factor a trinomial.
21((-2 + -1x)(1 + -1x)) = 0

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

Simplifying
1 + -1x = 0

Solving
1 + -1x = 0

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

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

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

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

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

Simplifying
x = 1
Solution
x = {-2, 1}