Answer:
The surface area is 664 cm²
Step-by-step explanation:
[tex]A=a^{2} +2a\sqrt{\frac{a^{2}}{4} } +h^{2}[/tex] Use this equation to find the surface area
[tex]A=18^{2} +2(18)\sqrt{\frac{18^{2}}{4} } +4^{2}[/tex] Simplify
[tex]A=324 +36\sqrt{\frac{324}{4} } +16[/tex] Simplify
A = 324 + 36√81 + 16 Simplify
A = 324 + 36(9) + 16 Simplify
A = 324 + 324 + 16 Simplify
A = 664 cm²
