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