Module · Geometry
Chapter 21: Quadrilaterals & Polygons
Geometry
4 topics
What this chapter covers
The 4 topics below make up Quadrilaterals & Polygons on the GRE. Click any topic to open its notes, examples and practice test.
Study material & tests
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Formula Reference Sheet
This chapter
Polygon angles
| Sum of interior angles (n sides) | (n − 2) × 180° |
|---|---|
| Each interior angle, regular polygon | (n − 2) × 180° / n |
| Sum of exterior angles | 360° (any polygon) |
| Each exterior angle, regular polygon | 360° / n |
Area & perimeter
| Rectangle | Area = l × w, Perimeter = 2(l + w) |
|---|---|
| Square, side s | Area = s², Perimeter = 4s |
| Parallelogram | Area = base × height |
| Trapezoid | Area = ½ (b₁ + b₂) × height |
GRE reference
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