A=115+1/2(p+s) solve for s
A = 115 + 1/2 (p + s)
you subtract 115 from both sides, and you get
A - 115 = 1/2 (p + s)
now you multiply by 2 on both sides, and you get
(A - 115) * 2 = p + s NOTE: I DISTRIBUTED 2 IN THE FOLLOWING EQUATION
now you subtract p on both sides to get s by itself and you get
2A - 230 - p = s
so the final answer is .......
\(s=2A-230-p\)