If Janey cuts the cube through the red line and separates the cube into two pieces, each piece will have one surface without paint.
The surfaces will be rectangular with length 8in and width 10in.
The area of the cut faces will be equal to:
[tex]\begin{gathered} A=w\cdot l \\ A=8\cdot10 \\ A=80in^2 \end{gathered}[/tex]
Since there are two cut faces to paint and both are equal, then their area is also equal. So the area she needs to paint is twice the calculated area:
[tex]\text{Total Area=2}\cdot80=160in^2[/tex]
