The length of the line segment of octagon which is AB equal to 3.4 cm.
Given that the area of the regular octagon is 54 [tex]cm^{2}[/tex], apothem of regular octagon is 4 cm. Line segment AB is side of the octagon.
We are required to find the length of the line segment AB.
A regular octagon has eight equal sides.
Area of regular octagon=Perimeter*apothem/2-----------1
We have to put the value of area and apothem in equation 1.
54=perimeter*4/2
Perimeter=(54*2)/4
=27 cm
Perimeter=27 cm.
Now we know that the perimeter is equal to the sum of the lengths of all sides of figure. So,
Perimeter=8*side
27=8*AB
AB=27/8
=3.375 cm
After rounding off it will be equal to 3.4 cm.
Hence the length of line segment is equal to 3.4 cm.
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