42=3(k+x)

Solution for 42=3(k+x) equation:

Simplifying
42 = 3(k + x)
42 = (k * 3 + x * 3)
42 = (3k + 3x)

Solving
42 = 3k + 3x

Solving for variable 'k'.

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

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

Combine like terms: 3k + -3k = 0
42 + -3k = 0 + 3x
42 + -3k = 3x

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

Combine like terms: 42 + -42 = 0
0 + -3k = -42 + 3x
-3k = -42 + 3x

Divide each side by '-3'.
k = 14 + -1x

Simplifying
k = 14 + -1x