Answer:
Total surface area = 485.4594 in
Step-by-step explanation:
Triangles area:
[tex]a = \frac{bh}{2} \\ h = 9 \cos(45) \\ h = 9.363961 \\ a = \frac{15 \times 9.363961}{2} \\ a = 47.7297[/tex]
rectangles area:
[tex]a = 10 \times 12 \\ a = 120[/tex]
and
[tex]a = 15 \times 10 \\ a = 150[/tex]
Total surface area:
[tex]a = 2(47.7297) + 2(120) + 150 \\ a = 95.4594 + 240 + 150 \\ a = 485.4594[/tex]
