Show that Eqs. (3-3) and (3-4) are valid for a column with two feeds (e.g., shown in Figure 4-18) as long as we define \(\mathrm{F}_{\text {total }}=\mathrm{F}_{1}+\mathrm{F}_{2}\) and \(\mathrm{z}_{\text {total }}=\left(\mathrm{F}_{1} \mathrm{z}_{1}\right.\) \(\left.+\mathrm{F}_{2} \mathrm{z}_{2}\right) / \mathrm{F}_{\text {total }} \cdot\)

Equation (3-3)

Equation (4-4)

Figure 18

D Z-XB XD-XB F