8-(9+a)=

Solution for 8-(9+a)= equation:

Simplifying
8 + -1(9 + a) = 0
8 + (9 * -1 + a * -1) = 0
8 + (-9 + -1a) = 0

Combine like terms: 8 + -9 = -1
-1 + -1a = 0

Solving
-1 + -1a = 0

Solving for variable 'a'.

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

Add '1' to each side of the equation.
-1 + 1 + -1a = 0 + 1

Combine like terms: -1 + 1 = 0
0 + -1a = 0 + 1
-1a = 0 + 1

Combine like terms: 0 + 1 = 1
-1a = 1

Divide each side by '-1'.
a = -1

Simplifying
a = -1