(4x+12)(x-3)=

Solution for (4x+12)(x-3)= equation:

Simplifying
(4x + 12)(x + -3) = 0

Reorder the terms:
(12 + 4x)(x + -3) = 0

Reorder the terms:
(12 + 4x)(-3 + x) = 0

Multiply (12 + 4x) * (-3 + x)
(12(-3 + x) + 4x * (-3 + x)) = 0
((-3 * 12 + x * 12) + 4x * (-3 + x)) = 0
((-36 + 12x) + 4x * (-3 + x)) = 0
(-36 + 12x + (-3 * 4x + x * 4x)) = 0
(-36 + 12x + (-12x + 4x2)) = 0

Combine like terms: 12x + -12x = 0
(-36 + 0 + 4x2) = 0
(-36 + 4x2) = 0

Solving
-36 + 4x2 = 0

Solving for variable 'x'.

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

Add '36' to each side of the equation.
-36 + 36 + 4x2 = 0 + 36

Combine like terms: -36 + 36 = 0
0 + 4x2 = 0 + 36
4x2 = 0 + 36

Combine like terms: 0 + 36 = 36
4x2 = 36

Divide each side by '4'.
x2 = 9

Simplifying
x2 = 9

Take the square root of each side:
x = {-3, 3}