7n-(6-2n)=21

Solution for 7n-(6-2n)=21 equation:

Simplifying
7n + -1(6 + -2n) = 21
7n + (6 * -1 + -2n * -1) = 21
7n + (-6 + 2n) = 21

Reorder the terms:
-6 + 7n + 2n = 21

Combine like terms: 7n + 2n = 9n
-6 + 9n = 21

Solving
-6 + 9n = 21

Solving for variable 'n'.

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

Add '6' to each side of the equation.
-6 + 6 + 9n = 21 + 6

Combine like terms: -6 + 6 = 0
0 + 9n = 21 + 6
9n = 21 + 6

Combine like terms: 21 + 6 = 27
9n = 27

Divide each side by '9'.
n = 3

Simplifying
n = 3