Quadrilaterals, which have 4 sides, are not the same as triangles which have 3 sides. Some similarity exists in that both are geometrical figures.
Quadrilaterals are polygons with four sides. Triangles are polygons with three sides.
Not true because all quadrilaterals contain 2 triangles
No because all triangles have only 3 sides whereas quadrilaterals have 4 sides.
Quadrilaterals, pentagons, triangles, octagons, hexagons, decagons.
They are both polygons.
In general, no.
Rhombus
Yes
No. Although for some 2-dimensional figures - some triangles and quadrilaterals - the term may be used in that way.
A square
The reguar polygons are triangles, quadrilaterals and hexagons.