# Find the surface area of a hexagonal prism with height of 12 cm and side length of 9 cm. Its geometry and i dont remember how to do it. Please include all the steps and the answer you got. Thanks.

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The surface area is the perimeter of the base multiplied by the height added to twice of the area of the base

SA = P*h + 2B

We'll calculate the perimeter of the base:

p = 6*l, where l = 9 cm

P = 6*9

P = 54 cm

We'll multiply the perimeter by the height:

P*h = 54 cm*12 cm = 648 cm^2

Now, we'll calculate the area of the base:

B = 3*l^2*sqrt3/2

l = 9 cm

B = 3*81*sqrt3/2

B = 121.5*sqrt3

2B= 2*121.5*sqrt3

2B = 243*sqrt3

Now, we'll gather all the results and we'll compute the surface area of the hexagonal prism:

SA = 648 + 243*sqrt3

**SA = 1068.39 cm^2**