0=-(x-9)(x-19)

Solution for 0=-(x-9)(x-19) equation:

Simplifying
0 = -1(x + -9)(x + -19)

Reorder the terms:
0 = -1(-9 + x)(x + -19)

Reorder the terms:
0 = -1(-9 + x)(-19 + x)

Multiply (-9 + x) * (-19 + x)
0 = -1(-9(-19 + x) + x(-19 + x))
0 = -1((-19 * -9 + x * -9) + x(-19 + x))
0 = -1((171 + -9x) + x(-19 + x))
0 = -1(171 + -9x + (-19 * x + x * x))
0 = -1(171 + -9x + (-19x + x2))

Combine like terms: -9x + -19x = -28x
0 = -1(171 + -28x + x2)
0 = (171 * -1 + -28x * -1 + x2 * -1)
0 = (-171 + 28x + -1x2)

Solving
0 = -171 + 28x + -1x2

Solving for variable 'x'.

Combine like terms: 0 + 171 = 171
171 + -28x + x2 = -171 + 28x + -1x2 + 171 + -28x + x2

Reorder the terms:
171 + -28x + x2 = -171 + 171 + 28x + -28x + -1x2 + x2

Combine like terms: -171 + 171 = 0
171 + -28x + x2 = 0 + 28x + -28x + -1x2 + x2
171 + -28x + x2 = 28x + -28x + -1x2 + x2

Combine like terms: 28x + -28x = 0
171 + -28x + x2 = 0 + -1x2 + x2
171 + -28x + x2 = -1x2 + x2

Combine like terms: -1x2 + x2 = 0
171 + -28x + x2 = 0

Factor a trinomial.
(9 + -1x)(19 + -1x) = 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 '(19 + -1x)' equal to zero and attempt to solve:

Simplifying
19 + -1x = 0

Solving
19 + -1x = 0

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

Add '-19' to each side of the equation.
19 + -19 + -1x = 0 + -19

Combine like terms: 19 + -19 = 0
0 + -1x = 0 + -19
-1x = 0 + -19

Combine like terms: 0 + -19 = -19
-1x = -19

Divide each side by '-1'.
x = 19

Simplifying
x = 19
Solution
x = {9, 19}