Expression 12: "L" Subscript, 1 , Baseline equals "A" Subscript, 1 , Baseline plus StartFraction, 2 left parenthesis, "B" Subscript, 1 , Baseline minus "A" Subscript, 1 , Baseline , right parenthesis Over 2 plus 1.4 , EndFractionL1=A1+2B1−A12+1.4