42=3-3n

Solution for 42=3-3n equation:

Simplifying
42 = 3 + -3n

Solving
42 = 3 + -3n

Solving for variable 'n'.

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

Add '3n' to each side of the equation.
42 + 3n = 3 + -3n + 3n

Combine like terms: -3n + 3n = 0
42 + 3n = 3 + 0
42 + 3n = 3

Add '-42' to each side of the equation.
42 + -42 + 3n = 3 + -42

Combine like terms: 42 + -42 = 0
0 + 3n = 3 + -42
3n = 3 + -42

Combine like terms: 3 + -42 = -39
3n = -39

Divide each side by '3'.
n = -13

Simplifying
n = -13