9-3=[4(a+5)-3a]

Solution for 9-3=[4(a+5)-3a] equation:

Simplifying
9 + -3 = [4(a + 5) + -3a]

Combine like terms: 9 + -3 = 6
6 = [4(a + 5) + -3a]

Reorder the terms:
6 = [4(5 + a) + -3a]
6 = [(5 * 4 + a * 4) + -3a]
6 = [(20 + 4a) + -3a]

Combine like terms: 4a + -3a = 1a
6 = [20 + 1a]

Remove brackets around [20 + 1a]
6 = 20 + 1a

Solving
6 = 20 + 1a

Solving for variable 'a'.

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

Add '-1a' to each side of the equation.
6 + -1a = 20 + 1a + -1a

Combine like terms: 1a + -1a = 0
6 + -1a = 20 + 0
6 + -1a = 20

Add '-6' to each side of the equation.
6 + -6 + -1a = 20 + -6

Combine like terms: 6 + -6 = 0
0 + -1a = 20 + -6
-1a = 20 + -6

Combine like terms: 20 + -6 = 14
-1a = 14

Divide each side by '-1'.
a = -14

Simplifying
a = -14