2[s+3(s-1)]=-18

Solution for 2[s+3(s-1)]=-18 equation:

Simplifying
2[s + 3(s + -1)] = -18

Reorder the terms:
2[s + 3(-1 + s)] = -18
2[s + (-1 * 3 + s * 3)] = -18
2[s + (-3 + 3s)] = -18

Reorder the terms:
2[-3 + s + 3s] = -18

Combine like terms: s + 3s = 4s
2[-3 + 4s] = -18
[-3 * 2 + 4s * 2] = -18
[-6 + 8s] = -18

Solving
-6 + 8s = -18

Solving for variable 's'.

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

Add '6' to each side of the equation.
-6 + 6 + 8s = -18 + 6

Combine like terms: -6 + 6 = 0
0 + 8s = -18 + 6
8s = -18 + 6

Combine like terms: -18 + 6 = -12
8s = -12

Divide each side by '8'.
s = -1.5

Simplifying
s = -1.5