



 
Hi Katy, You said hexagon and then in the same sentence pentagon and I wasn't sure which you wanted so I decided to use an octagon. Inscribe a regular octagon in a circle. Join each vertex of the octagon to the centre of the circle.
The octagon is thus partitioned into eight isosceles triangles, each with a central angle of measure 360/8 = 45 degrees and two sides of length 6.72 centimeters. Can you find the length of the third side? Penny  


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