-2(a+3)-a=10

Solution for -2(a+3)-a=10 equation:

Simplifying
-2(a + 3) + -1a = 10

Reorder the terms:
-2(3 + a) + -1a = 10
(3 * -2 + a * -2) + -1a = 10
(-6 + -2a) + -1a = 10

Combine like terms: -2a + -1a = -3a
-6 + -3a = 10

Solving
-6 + -3a = 10

Solving for variable 'a'.

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

Add '6' to each side of the equation.
-6 + 6 + -3a = 10 + 6

Combine like terms: -6 + 6 = 0
0 + -3a = 10 + 6
-3a = 10 + 6

Combine like terms: 10 + 6 = 16
-3a = 16

Divide each side by '-3'.
a = -5.333333333

Simplifying
a = -5.333333333