42=3n+0.5n

Solution for 42=3n+0.5n equation:

Simplifying
42 = 3n + 0.5n

Combine like terms: 3n + 0.5n = 3.5n
42 = 3.5n

Solving
42 = 3.5n

Solving for variable 'n'.

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

Add '-3.5n' to each side of the equation.
42 + -3.5n = 3.5n + -3.5n

Combine like terms: 3.5n + -3.5n = 0.0
42 + -3.5n = 0.0

Add '-42' to each side of the equation.
42 + -42 + -3.5n = 0.0 + -42

Combine like terms: 42 + -42 = 0
0 + -3.5n = 0.0 + -42
-3.5n = 0.0 + -42

Combine like terms: 0.0 + -42 = -42
-3.5n = -42

Divide each side by '-3.5'.
n = 12

Simplifying
n = 12