216=(x+5)(2x+4)

Solution for 216=(x+5)(2x+4) equation:

Simplifying
216 = (x + 5)(2x + 4)

Reorder the terms:
216 = (5 + x)(2x + 4)

Reorder the terms:
216 = (5 + x)(4 + 2x)

Multiply (5 + x) * (4 + 2x)
216 = (5(4 + 2x) + x(4 + 2x))
216 = ((4 * 5 + 2x * 5) + x(4 + 2x))
216 = ((20 + 10x) + x(4 + 2x))
216 = (20 + 10x + (4 * x + 2x * x))
216 = (20 + 10x + (4x + 2x2))

Combine like terms: 10x + 4x = 14x
216 = (20 + 14x + 2x2)

Solving
216 = 20 + 14x + 2x2

Solving for variable 'x'.

Combine like terms: 216 + -20 = 196
196 + -14x + -2x2 = 20 + 14x + 2x2 + -20 + -14x + -2x2

Reorder the terms:
196 + -14x + -2x2 = 20 + -20 + 14x + -14x + 2x2 + -2x2

Combine like terms: 20 + -20 = 0
196 + -14x + -2x2 = 0 + 14x + -14x + 2x2 + -2x2
196 + -14x + -2x2 = 14x + -14x + 2x2 + -2x2

Combine like terms: 14x + -14x = 0
196 + -14x + -2x2 = 0 + 2x2 + -2x2
196 + -14x + -2x2 = 2x2 + -2x2

Combine like terms: 2x2 + -2x2 = 0
196 + -14x + -2x2 = 0

Factor out the Greatest Common Factor (GCF), '2'.
2(98 + -7x + -1x2) = 0

Factor a trinomial.
2((7 + -1x)(14 + x)) = 0

Ignore the factor 2.
Subproblem 1
Set the factor '(7 + -1x)' equal to zero and attempt to solve:

Simplifying
7 + -1x = 0

Solving
7 + -1x = 0

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

Add '-7' to each side of the equation.
7 + -7 + -1x = 0 + -7

Combine like terms: 7 + -7 = 0
0 + -1x = 0 + -7
-1x = 0 + -7

Combine like terms: 0 + -7 = -7
-1x = -7

Divide each side by '-1'.
x = 7

Simplifying
x = 7
Subproblem 2
Set the factor '(14 + x)' equal to zero and attempt to solve:

Simplifying
14 + x = 0

Solving
14 + x = 0

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

Add '-14' to each side of the equation.
14 + -14 + x = 0 + -14

Combine like terms: 14 + -14 = 0
0 + x = 0 + -14
x = 0 + -14

Combine like terms: 0 + -14 = -14
x = -14

Simplifying
x = -14
Solution
x = {7, -14}