3(3-3k)+6(k+5)=42

Solution for 3(3-3k)+6(k+5)=42 equation:

Simplifying
3(3 + -3k) + 6(k + 5) = 42
(3 * 3 + -3k * 3) + 6(k + 5) = 42
(9 + -9k) + 6(k + 5) = 42

Reorder the terms:
9 + -9k + 6(5 + k) = 42
9 + -9k + (5 * 6 + k * 6) = 42
9 + -9k + (30 + 6k) = 42

Reorder the terms:
9 + 30 + -9k + 6k = 42

Combine like terms: 9 + 30 = 39
39 + -9k + 6k = 42

Combine like terms: -9k + 6k = -3k
39 + -3k = 42

Solving
39 + -3k = 42

Solving for variable 'k'.

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

Add '-39' to each side of the equation.
39 + -39 + -3k = 42 + -39

Combine like terms: 39 + -39 = 0
0 + -3k = 42 + -39
-3k = 42 + -39

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

Divide each side by '-3'.
k = -1

Simplifying
k = -1