In the rhombus ABCD there are segments AC and BD diagonals that intersect at point O

In the rhombus ABCD there are segments AC and BD diagonals that intersect at point O write down the names of a) triangles with a primitive angle b) triangles with an obtuse angle c) triangles in which all angles are acute

If in rhombus ABCD the large diagonal AC meets the diagonal BD at point O, then:

a) the following triangles are rectangular: AOB, BOC, COD and DOA – those formed by halves of diagonals intersecting at right angles;

b) triangles with an obtuse angle: ACD and ABD – one of the sides is the larger diagonal;

c) triangles in which all corners are sharp: BAD and BCD – half a rhombus, separated by a smaller diagonal.

Everything described is possible if the rhombus is not a square.