[table][tr][td]1[/td][td]Draw the squares 1EF4 and E23F.[/td][/tr][tr][td]2[/td][td]Define the centers G and H of both squares.[/td][/tr][tr][td]3[/td][td]Construct the circular arcs from 1 to 4 with midpoint G and from 2 to 3 to midpoint H.[/td][/tr][/table]