-3(1+2a)+3(8a-1)=12

Solution for -3(1+2a)+3(8a-1)=12 equation:

Simplifying
-3(1 + 2a) + 3(8a + -1) = 12
(1 * -3 + 2a * -3) + 3(8a + -1) = 12
(-3 + -6a) + 3(8a + -1) = 12

Reorder the terms:
-3 + -6a + 3(-1 + 8a) = 12
-3 + -6a + (-1 * 3 + 8a * 3) = 12
-3 + -6a + (-3 + 24a) = 12

Reorder the terms:
-3 + -3 + -6a + 24a = 12

Combine like terms: -3 + -3 = -6
-6 + -6a + 24a = 12

Combine like terms: -6a + 24a = 18a
-6 + 18a = 12

Solving
-6 + 18a = 12

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 + 18a = 12 + 6

Combine like terms: -6 + 6 = 0
0 + 18a = 12 + 6
18a = 12 + 6

Combine like terms: 12 + 6 = 18
18a = 18

Divide each side by '18'.
a = 1

Simplifying
a = 1