



 
Hello Sara, Let’s try to draw a picture of this situation. We will forget about the depth of the pan for now to simplify the picture since it makes no difference. Well, the sides of the square are 24 cm, so if we call the length of the sides of the triangles cut out of the cake to be, x, then the side of the octagon is 24  2x. (Why?) We also know that the triangle is a right triangle (how?), so we can use the Pythagorean theorem to determine the length of the hypotenuse. Since the octagon is regular, these formulae must be equal, so set them equal and solve for x. Tyler  


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