(X+11)+(x+9)=30

Solution for (X+11)+(x+9)=30 equation:

Simplifying
(X + 11) + (x + 9) = 30

Reorder the terms:
(11 + X) + (x + 9) = 30

Remove parenthesis around (11 + X)
11 + X + (x + 9) = 30

Reorder the terms:
11 + X + (9 + x) = 30

Remove parenthesis around (9 + x)
11 + X + 9 + x = 30

Reorder the terms:
11 + 9 + X + x = 30

Combine like terms: 11 + 9 = 20
20 + X + x = 30

Solving
20 + X + x = 30

Solving for variable 'X'.

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

Add '-20' to each side of the equation.
20 + X + -20 + x = 30 + -20

Reorder the terms:
20 + -20 + X + x = 30 + -20

Combine like terms: 20 + -20 = 0
0 + X + x = 30 + -20
X + x = 30 + -20

Combine like terms: 30 + -20 = 10
X + x = 10

Add '-1x' to each side of the equation.
X + x + -1x = 10 + -1x

Combine like terms: x + -1x = 0
X + 0 = 10 + -1x
X = 10 + -1x

Simplifying
X = 10 + -1x