If you don’t have a 60 degree ruler but your ruler or your mat has 60 degree markings, this is how you can cut equilateral triangles.
How to cut equilateral triangles with a regular ruler
This 2 minute video shows you how to cut equilateral triangles in 3 ways without using special rulers:
With this type of triangle you can make lots of different quick quilts.
One of my favourite blocks you can do with equilateral triangles is a hexagon block.