| Plane axes |
| Familiar axes |
| Standard axes |
| Dual variables |
| Common graph axes |
| Algebraic unknowns |
| 2005 Coldplay album |
| Standard graph axes |
| Unknowns in algebra |
| Axes in a geometry class |
| 2005 #1 album for Coldplay |
| Simultaneous equation unknowns |
| Simultaneous equation variables |
| Things to solve for, in some equations |
| 2005 Coldplay album with the single "Speed of Sound |