(x+5)(4x-12)=0

Solution for (x+5)(4x-12)=0 equation:

Simplifying
(x + 5)(4x + -12) = 0

Reorder the terms:
(5 + x)(4x + -12) = 0

Reorder the terms:
(5 + x)(-12 + 4x) = 0

Multiply (5 + x) * (-12 + 4x)
(5(-12 + 4x) + x(-12 + 4x)) = 0
((-12 * 5 + 4x * 5) + x(-12 + 4x)) = 0
((-60 + 20x) + x(-12 + 4x)) = 0
(-60 + 20x + (-12 * x + 4x * x)) = 0
(-60 + 20x + (-12x + 4x2)) = 0

Combine like terms: 20x + -12x = 8x
(-60 + 8x + 4x2) = 0

Solving
-60 + 8x + 4x2 = 0

Solving for variable 'x'.

Factor out the Greatest Common Factor (GCF), '4'.
4(-15 + 2x + x2) = 0

Factor a trinomial.
4((-5 + -1x)(3 + -1x)) = 0

Ignore the factor 4.
Subproblem 1
Set the factor '(-5 + -1x)' equal to zero and attempt to solve:

Simplifying
-5 + -1x = 0

Solving
-5 + -1x = 0

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

Add '5' to each side of the equation.
-5 + 5 + -1x = 0 + 5

Combine like terms: -5 + 5 = 0
0 + -1x = 0 + 5
-1x = 0 + 5

Combine like terms: 0 + 5 = 5
-1x = 5

Divide each side by '-1'.
x = -5

Simplifying
x = -5
Subproblem 2
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
Solution
x = {-5, 3}