(x-20)(x-18)=0

Solution for (x-20)(x-18)=0 equation:

Simplifying
(x + -20)(x + -18) = 0

Reorder the terms:
(-20 + x)(x + -18) = 0

Reorder the terms:
(-20 + x)(-18 + x) = 0

Multiply (-20 + x) * (-18 + x)
(-20(-18 + x) + x(-18 + x)) = 0
((-18 * -20 + x * -20) + x(-18 + x)) = 0
((360 + -20x) + x(-18 + x)) = 0
(360 + -20x + (-18 * x + x * x)) = 0
(360 + -20x + (-18x + x2)) = 0

Combine like terms: -20x + -18x = -38x
(360 + -38x + x2) = 0

Solving
360 + -38x + x2 = 0

Solving for variable 'x'.

Factor a trinomial.
(18 + -1x)(20 + -1x) = 0

Subproblem 1
Set the factor '(18 + -1x)' equal to zero and attempt to solve:

Simplifying
18 + -1x = 0

Solving
18 + -1x = 0

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

Add '-18' to each side of the equation.
18 + -18 + -1x = 0 + -18

Combine like terms: 18 + -18 = 0
0 + -1x = 0 + -18
-1x = 0 + -18

Combine like terms: 0 + -18 = -18
-1x = -18

Divide each side by '-1'.
x = 18

Simplifying
x = 18
Subproblem 2
Set the factor '(20 + -1x)' equal to zero and attempt to solve:

Simplifying
20 + -1x = 0

Solving
20 + -1x = 0

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

Add '-20' to each side of the equation.
20 + -20 + -1x = 0 + -20

Combine like terms: 20 + -20 = 0
0 + -1x = 0 + -20
-1x = 0 + -20

Combine like terms: 0 + -20 = -20
-1x = -20

Divide each side by '-1'.
x = 20

Simplifying
x = 20
Solution
x = {18, 20}