GRE Quant · Chapter Test
Triangles — 25-Question Test
A fresh, mixed-difficulty set drawn from the whole chapter — questions you haven't been asked before. Auto-graded with full solutions; your result is saved to your dashboard.
Building your 25-question test…
Formula Reference Sheet
This chapter
Angles & sides
| Angle sum of a triangle | a + b + c = 180° |
|---|---|
| Exterior angle | = sum of the two remote interior angles |
| Triangle inequality | |a − b| < third side < a + b |
| Isosceles | equal sides ⇒ equal base angles |
Right triangles
| Pythagorean theorem | a² + b² = c² (c = hypotenuse) |
|---|---|
| Common triples | 3-4-5, 5-12-13, 8-15-17, 7-24-25 (and multiples) |
| 45-45-90 sides | 1 : 1 : √2 (leg : leg : hypotenuse) |
| 30-60-90 sides | 1 : √3 : 2 (opposite 30° : 60° : 90°) |
Area
| Any triangle | Area = ½ × base × height |
|---|---|
| Equilateral, side s | Area = (√3 / 4) × s² |
GRE reference
🖩 Graphing Calculator