Classifying 2-Dimensional Figures

A triangle with all angles less than 90 degrees

• acute

• right

• obtuse

A triangle with one 90 degree angle

• right triangle

• obtuse triangle

• acute triangle

a triangle with one angle over 90 degrees

• obtuse triangle

• acute triangle

• right triangle

opposite sides are parallel and equal

• quadrilateral

• parallelogram

• trapezoid

• polygon

parallelogram with 4 right angles

• rhombus

• rectangle

• quadrilateral

• polygon

parallelogram with 4 right angles and 4 equal sides

• parallelogram

• rectangle

• square

• rhombus

parallelogram with 4 equal sides

• square

• rectangle

• trapezoid

• rhombus

exactly one pair of parallel sides

• square

• rectangle

• triangle

• trapezoid

polygon with 4 sides

• quadrilateral

• pentagon

• hectagon

• octagon

polygon with 5 sides

• quadrilateral

• octagon

• hexagon

• pentagon