Angles, Triangles, and Quadrangles

1. Angles

1.1. Vertex

1.2. Obtuse

1.3. Acute

1.4. Right Angle

2. Triangles

2.1. Obtuse Triangle

2.2. Acute Triangle

2.3. Equilateral Triangle

3. Quadrangle

3.1. Square

3.2. Rhombus

3.3. Rectangle

3.4. Parallelogram

3.5. Trapezoid