-[2]=6+u

Solution for -[2]=6+u equation:

Simplifying
-1[2] = 6 + u

Multiply -1 * 2
-2 = 6 + u

Solving
-2 = 6 + u

Solving for variable 'u'.

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

Add '-1u' to each side of the equation.
-2 + -1u = 6 + u + -1u

Combine like terms: u + -1u = 0
-2 + -1u = 6 + 0
-2 + -1u = 6

Add '2' to each side of the equation.
-2 + 2 + -1u = 6 + 2

Combine like terms: -2 + 2 = 0
0 + -1u = 6 + 2
-1u = 6 + 2

Combine like terms: 6 + 2 = 8
-1u = 8

Divide each side by '-1'.
u = -8

Simplifying
u = -8