Michelle created an octagonal quilt piece for a quilt making class project. it was cut from a square with a side length of 10 cm. To make the piece, Michelle cut off the four corners of the square, by measuring 2.9 cm from each corner, and then cutting the diagonal. What are the area and perimeter of the octagonal quilt piece?
+33661 The four corners are triangles each of side 2.9 cm and diagonal sqrt(2)*2.9 cm
They can be put together to make two squares each of area 2.9^2 cm^2, so the area of the octagon is the area of the original square less the area of the 4 triangles, namely:
Area = 10^2 - 2*2.9^2 cm^2
Perimeter = 4*sqrt(2)*2.9 + 4*(10 - 2*2.9) cm
I'll leave you to do the number crunching.
