all three angles in an equilateral triangle are 60 degrees -
the name implies that all three sides are equal - which they are - in a triangle with all three angles the same (60 degrees)
I used to think that the angles in Dorene Speckman's Peaky and Spike pieces were 30, 90, and 60 degrees. They aren't.
The three components make a square.
They side pieces are approximately 26.6 and 63.4 degrees, with 90 degree corners. The center part of that block is an isosceles triangle with angles of 26.4, 26.4 and 128.8 degrees.
It's actually just simpler to make a square and draw in the lines for this "block".
The reason for writing this is to advise AGAINST using a 30, 60, 90 triangle for this. I thought it would work, and it didn't.