"triangles" - key terms from Wikipedia

black triangles
congruence of triangles
dayton triangles
episode triangles
equilateral triangles
pairs of triangles
raster triangles
right triangles
robinson triangles
set of triangles
similar triangles
spherical triangles
then the triangles	are congruent
triangles
triangles	are similar
two triangles
two triangles	are equal
types of triangles
velocity triangles