Surface Area

1. Finally, we add the area of all 5 faces. The surface area of the rectangular prism can be found with the following expression:

$100+40+40+40+40$

2. There are six square faces with an area of 16 square units each. The following expression represents the surface area of the cube.

$6 \cdot 16$

3. Finally, we add the area of all 5 faces.

$24+24+120+160+200$

The following expression represents the surface area of the triangular prism.

$2 \cdot 24+120+160+200$

4. Finally, we add the area of all 6 faces.

$15+15+30+30+18+18$

The following expression represents the surface area of the rectangular prism.

$2 \cdot 15+2 \cdot 30+2 \cdot 18$