12-(-m+9)=y

Solution for 12-(-m+9)=y equation:

Simplifying
12 + -1(-1m + 9) = y

Reorder the terms:
12 + -1(9 + -1m) = y
12 + (9 * -1 + -1m * -1) = y
12 + (-9 + 1m) = y

Combine like terms: 12 + -9 = 3
3 + 1m = y

Solving
3 + 1m = y

Solving for variable 'm'.

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

Add '-3' to each side of the equation.
3 + -3 + 1m = -3 + y

Combine like terms: 3 + -3 = 0
0 + 1m = -3 + y
1m = -3 + y

Divide each side by '1'.
m = -3 + y

Simplifying
m = -3 + y