(x+2)(x-1)=4

Solution for (x+2)(x-1)=4 equation:

Simplifying
(x + 2)(x + -1) = 4

Reorder the terms:
(2 + x)(x + -1) = 4

Reorder the terms:
(2 + x)(-1 + x) = 4

Multiply (2 + x) * (-1 + x)
(2(-1 + x) + x(-1 + x)) = 4
((-1 * 2 + x * 2) + x(-1 + x)) = 4
((-2 + 2x) + x(-1 + x)) = 4
(-2 + 2x + (-1 * x + x * x)) = 4
(-2 + 2x + (-1x + x2)) = 4

Combine like terms: 2x + -1x = 1x
(-2 + 1x + x2) = 4

Solving
-2 + 1x + x2 = 4

Solving for variable 'x'.

Reorder the terms:
-2 + -4 + 1x + x2 = 4 + -4

Combine like terms: -2 + -4 = -6
-6 + 1x + x2 = 4 + -4

Combine like terms: 4 + -4 = 0
-6 + 1x + x2 = 0

Factor a trinomial.
(-3 + -1x)(2 + -1x) = 0

Subproblem 1
Set the factor '(-3 + -1x)' equal to zero and attempt to solve:

Simplifying
-3 + -1x = 0

Solving
-3 + -1x = 0

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

Add '3' to each side of the equation.
-3 + 3 + -1x = 0 + 3

Combine like terms: -3 + 3 = 0
0 + -1x = 0 + 3
-1x = 0 + 3

Combine like terms: 0 + 3 = 3
-1x = 3

Divide each side by '-1'.
x = -3

Simplifying
x = -3
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 = {-3, 2}