20=(x+4)+y

Solution for 20=(x+4)+y equation:

Simplifying
20 = (x + 4) + y

Reorder the terms:
20 = (4 + x) + y

Remove parenthesis around (4 + x)
20 = 4 + x + y

Solving
20 = 4 + x + y

Solving for variable 'x'.

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

Add '-1x' to each side of the equation.
20 + -1x = 4 + x + -1x + y

Combine like terms: x + -1x = 0
20 + -1x = 4 + 0 + y
20 + -1x = 4 + y

Add '-20' to each side of the equation.
20 + -20 + -1x = 4 + -20 + y

Combine like terms: 20 + -20 = 0
0 + -1x = 4 + -20 + y
-1x = 4 + -20 + y

Combine like terms: 4 + -20 = -16
-1x = -16 + y

Divide each side by '-1'.
x = 16 + -1y

Simplifying
x = 16 + -1y