At 151°, this is an obtuse angle, opened up past a square corner but not yet flat. Its supplement is 29°, so a 151° angle and a 29° angle side by side make a straight line.
151° is 151/360 of a full circle, or 151π/180 radians. If you face north and turn 151° clockwise, you end up facing between SE and SSE (closest to south-southeast (SSE)).
151° angle facts
| Angle type | Obtuse angle (between 90° and 180°) |
|---|---|
| Supplement (adds to 180°) | 29° |
| Explement (adds to 360°) | 209° |
| Radians | 151π/180 ≈ 2.635447 |
| Gradians | 167.7778 grad |
| Fraction of a turn | 151/360 (41.94%) |
| Degrees, minutes, seconds | 151° 0′ 0″ |
| Compass bearing | between SE and SSE (closest to south-southeast (SSE)) |
Trigonometric values of 151°
| Function | Value |
|---|---|
| sin 151° | 0.48481 |
| cos 151° | −0.87462 |
| tan 151° | −0.554309 |
151° on a protractor
How to draw a 151° angle with a protractor
- Draw a straight line with a ruler. This is the first arm; mark the vertex at one end.
- Place the center mark of the protractor exactly on the vertex and line up the 0° baseline with your line.
- Find 151° on the row of numbers that reads 0° on your line (protractors have two rows running in opposite directions) and make a small dot at the edge.
- Remove the protractor and draw a line from the vertex through the dot. Mark the angle with an arc and label it 151°.
Drawing it a 151° angle without a protractor (rise and run method)
- 151° = 180° − 29°. Draw a straight line, pick a vertex on it, and build a 29° angle on one side as follows; the angle on the other side of the new line is 151°.
- Draw a straight baseline and measure exactly 10 inches along it from the vertex.
- At the 10-inch mark, draw a short line straight up at 90° (use a carpenter's square or the corner of a sheet of paper).
- Measure 5.54 inches (about 5 9/16″) up that line and make a mark.
- Join the mark to the vertex. The angle at the vertex is 29°, because tan 29° ≈ 0.5543.
Where you see 151° angles
- The Earth turns 151° on its axis in about 10 h 4 min.
- Obtuse angles like 151° appear in reclining chair backs, open laptop screens, fan blades, and the corners of many-sided polygons.
Related angles
151° angle FAQ
What type of angle is 151°?
A 151° angle is an obtuse angle, because it is between 90° and 180°.
What is the supplement of 151°?
The supplement of 151° is 29°, because 151° + 29° = 180°. A 151° angle has no complement, because it is already larger than 90°.
How many radians is 151 degrees?
151° = 151π/180 radians ≈ 2.6354 rad. To convert degrees to radians, multiply by π/180: 151 × π/180 = 151π/180.
How do I measure a 151° angle on my screen?
Open the online protractor with 151° preset, or type 151 into its "Type an angle" box. You can then drag the arms onto your own lines to compare.
