Hello
The formula of the total surface area of this figure is
[tex]\begin{gathered} 2lw+2lh+2hw \\ 2(5\times x)+2(3\times5)+2(x\times5) \\ 10x+30+10x=20x+30 \end{gathered}[/tex]
The total surface area of this figure is 20x + 30
The polynomial that represents the total surface area of the figure is
20x + 30.
Now we have to find the surface area of figure a
3 by 5 by 3
The surface area for figure a is
[tex]2(3\times5)+2(5\times3)+2(3\times3)=78units^2[/tex]
The surface area for figure b is
3 by 5 by 5
[tex]2(3\times5)+2(5\times5)+2(5\times3)=110units^2_{}[/tex]
The surface area of figure c is
3 by 5 by 12
[tex]2(3\times5)+2(3\times12)+2(5\times12)=222units^2[/tex]
The surface area for figure d is
3 by 5 by 14
[tex]2(3\times5)+2(5\times14)+2(3\times14)=254units_{}[/tex]
From the calculations above, the surface area of figure a, b, c and d are 78 units, 110 units, 222 units and 254 units respectively
