Find the total surface area of the solid.
The faces of this solid are
1 rectangle 8 cm × 20 cm;
1 rectangle 17 cm × 20 cm;
1 rectangle 15 cm × 20 cm;
2 triangular bases (right triangles). The area of each one is
(8 cm × 15 cm)/2.
Total surface area:
A = 8 × 20 + 17 × 20 + 15 × 20 + 2 × [ (8 × 15)/2 ]
A = 160 + 340 + 300 + 120
A = 920 cm^2 <——— this is the answer.
I hope this helps. =)