Question

A stop sign — a regular octagon — can be formed from a 12-inch square sheet of metal by making four straight cuts that snip off the corners. How long, to the nearest 0.01 inch, are the sides of the resulting polygon?

Answer 1

\[12-2x=x \sqrt{2},2x+x \sqrt{2}=12\]
\[x \left( 2+\sqrt{2} \right)=12,x=\frac{ 12 }{ 2+\sqrt{2} }\]
rationalize both sides and find x and then 12-2x .