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carolinagurl95
Find the area of a regular octagon with apothem K and side of 10. 40K 60K 80K
For a regular octagon the area is given by \[8 × \text {Apothem}^2 × \tan(π/8) \] Again, \[\text{Side} = 2 × \text{ Apothem } × \tan(π/8) \] So use the second one to find the value of tan(π/8) and then substitute the value in the first which will give 40k as answer.