(c-11)(c-9)=

Solution for (c-11)(c-9)= equation:

Simplifying
(c + -11)(c + -9) = 0

Reorder the terms:
(-11 + c)(c + -9) = 0

Reorder the terms:
(-11 + c)(-9 + c) = 0

Multiply (-11 + c) * (-9 + c)
(-11(-9 + c) + c(-9 + c)) = 0
((-9 * -11 + c * -11) + c(-9 + c)) = 0
((99 + -11c) + c(-9 + c)) = 0
(99 + -11c + (-9 * c + c * c)) = 0
(99 + -11c + (-9c + c2)) = 0

Combine like terms: -11c + -9c = -20c
(99 + -20c + c2) = 0

Solving
99 + -20c + c2 = 0

Solving for variable 'c'.

Factor a trinomial.
(9 + -1c)(11 + -1c) = 0

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

Simplifying
9 + -1c = 0

Solving
9 + -1c = 0

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

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

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

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

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

Simplifying
c = 9
Subproblem 2
Set the factor '(11 + -1c)' equal to zero and attempt to solve:

Simplifying
11 + -1c = 0

Solving
11 + -1c = 0

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

Add '-11' to each side of the equation.
11 + -11 + -1c = 0 + -11

Combine like terms: 11 + -11 = 0
0 + -1c = 0 + -11
-1c = 0 + -11

Combine like terms: 0 + -11 = -11
-1c = -11

Divide each side by '-1'.
c = 11

Simplifying
c = 11
Solution
c = {9, 11}