525=(12+x)(16+x)

Solution for 525=(12+x)(16+x) equation:

Simplifying
525 = (12 + x)(16 + x)

Multiply (12 + x) * (16 + x)
525 = (12(16 + x) + x(16 + x))
525 = ((16 * 12 + x * 12) + x(16 + x))
525 = ((192 + 12x) + x(16 + x))
525 = (192 + 12x + (16 * x + x * x))
525 = (192 + 12x + (16x + x2))

Combine like terms: 12x + 16x = 28x
525 = (192 + 28x + x2)

Solving
525 = 192 + 28x + x2

Solving for variable 'x'.

Combine like terms: 525 + -192 = 333
333 + -28x + -1x2 = 192 + 28x + x2 + -192 + -28x + -1x2

Reorder the terms:
333 + -28x + -1x2 = 192 + -192 + 28x + -28x + x2 + -1x2

Combine like terms: 192 + -192 = 0
333 + -28x + -1x2 = 0 + 28x + -28x + x2 + -1x2
333 + -28x + -1x2 = 28x + -28x + x2 + -1x2

Combine like terms: 28x + -28x = 0
333 + -28x + -1x2 = 0 + x2 + -1x2
333 + -28x + -1x2 = x2 + -1x2

Combine like terms: x2 + -1x2 = 0
333 + -28x + -1x2 = 0

Factor a trinomial.
(9 + -1x)(37 + x) = 0

Subproblem 1
Set the factor '(9 + -1x)' equal to zero and attempt to solve:

Simplifying
9 + -1x = 0

Solving
9 + -1x = 0

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

Add '-9' to each side of the equation.
9 + -9 + -1x = 0 + -9

Combine like terms: 9 + -9 = 0
0 + -1x = 0 + -9
-1x = 0 + -9

Combine like terms: 0 + -9 = -9
-1x = -9

Divide each side by '-1'.
x = 9

Simplifying
x = 9
Subproblem 2
Set the factor '(37 + x)' equal to zero and attempt to solve:

Simplifying
37 + x = 0

Solving
37 + x = 0

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

Add '-37' to each side of the equation.
37 + -37 + x = 0 + -37

Combine like terms: 37 + -37 = 0
0 + x = 0 + -37
x = 0 + -37

Combine like terms: 0 + -37 = -37
x = -37

Simplifying
x = -37
Solution
x = {9, -37}