Answer
$2HC_{2}H_{3}O_{2}(aq)+ Ca(OH)_{2}(aq)\ -->\ 2H_{2}O(l)+ Ca(C_{2}H_{3}O_{2})_{2}(aq)$
Work Step by Step
The acid and base neutralize each other to form $H_{2}O$. To balance the equation, add a 2 to the $HC_{2}H_{3}O_{2}$ as there are two $C_{2}H_{3}O_{2}^{-}$ ions in the products. Then add a 2 to the $H_{2}O$ as there are two $H^{+}$ and $OH{-}$ ions in the reactions forming two $H_{2}O$ molecules.
