(n-9)*2=12

Solution for (n-9)*2=12 equation:

Simplifying
(n + -9) * 2 = 12

Reorder the terms:
(-9 + n) * 2 = 12

Reorder the terms for easier multiplication:
2(-9 + n) = 12
(-9 * 2 + n * 2) = 12
(-18 + 2n) = 12

Solving
-18 + 2n = 12

Solving for variable 'n'.

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

Add '18' to each side of the equation.
-18 + 18 + 2n = 12 + 18

Combine like terms: -18 + 18 = 0
0 + 2n = 12 + 18
2n = 12 + 18

Combine like terms: 12 + 18 = 30
2n = 30

Divide each side by '2'.
n = 15

Simplifying
n = 15