Margot is sewing a ribbon on a seam along the perimeter of a square pillow. the side length of the pillow is 2x2 + 1 inches, and its perimeter is 4(2x^2 + 1) inches. if x = 3.5, how much ribbon does she need?

Given information

Side length of a square = 2x² + 1
Perimeter of the square = 4(2x² + 1)


If x = 3.5, find perimeter

Perimeter of the square = 4(2(3.5)² +1)
Perimeter of the square = 4(2(12.25) +1)
Perimeter of the square = 4(24.5 +1)
Perimeter of the square = 4(25.5)
Perimeter of the square = 102 inches


Margot will need 102 inches of the ribbon.