(1/6)*s-((1/2)*(s-2)) = 45/2 // - 45/2
(1/6)*s-((1/2)*(s-2))-(45/2) = 0
(-1/2)*(s-2)+(1/6)*s-45/2 = 0
s/6-1/2*(s-2)-45/2 = 0
(-1/2*2*6*(s-2))/(2*6)+(2*s)/(2*6)+(-45*6)/(2*6) = 0
2*s-1/2*2*6*(s-2)-45*6 = 0
12-4*s-270 = 0
-4*s-258 = 0
(-4*s-258)/(2*6) = 0
(-4*s-258)/(2*6) = 0 // * 2*6
-4*s-258 = 0
-4*s-258 = 0 // + 258
-4*s = 258 // : -4
s = 258/(-4)
s = -129/2
s = -129/2
