# Math

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Find the surface area of a right octagonal pyramid with height 2.5 yards, and its base has apothem length 1.5 yards.

• Math -

Surface Area=Base Area+Lateral Area
SA=BA+LA
The side of the octagon
a=2*apothem*tan(45/2)
BA=0.5*8a*apothem=8*apothem^2*tan(45/2)
LA=4a*(slant height)
slant height=sqrt(height^2+apothem^2)

tan(45/2)=0.4142

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