I saw this pic so I did the large square (using my own measurements) and cut in 1/4s
Now I need to know how to figure making the side triangles.
The CUT squares measure 10.5 inches.

Here's a site that can help you:

http://www.atimetosewquilts.com/meas...#sidetriangles

Scroll down and you'll find it. :thumbup:

or, being a math major, the square of the hypotenuse equals the sum of the squares of the other two sides. 10.5 squared plus 10.5 squared = 220.5. the sq root of that is 14.849". i would round that up and add the seam allowances. thus, a 15.5" square can be cut diagonally to fit in the spot.

If you are setting your squares on point, the long side of the triangles should be on the straight of grain. So I would measure from point to point with the triangles laid out and cut a square that size and cut diagonally twice. This will give you 4 triangles.

If you cut a square diagonally into 2 triangles, your long side will be on the bias and could get wonky.

Thank you all.
I will post a pic when I finish.

Easy way..take freezer paper..lay it in the space..trace triangle..add 1/4 for seams on sides only..should fit right in !!

That is my way of thinking too>>>who needs all that math! :thumbup:

Huh?? ;)