15.5+3=s

Solution for 15.5+3=s equation:

Simplifying
15.5 + 3 = s

Combine like terms: 15.5 + 3 = 18.5
18.5 = s

Solving
18.5 = s

Solving for variable 's'.

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

Add '-1s' to each side of the equation.
18.5 + -1s = s + -1s

Combine like terms: s + -1s = 0
18.5 + -1s = 0

Add '-18.5' to each side of the equation.
18.5 + -18.5 + -1s = 0 + -18.5

Combine like terms: 18.5 + -18.5 = 0.0
0.0 + -1s = 0 + -18.5
-1s = 0 + -18.5

Combine like terms: 0 + -18.5 = -18.5
-1s = -18.5

Divide each side by '-1'.
s = 18.5

Simplifying
s = 18.5