A 179° angle is obtuse because it is greater than 90° and less than 180°. Its supplement is 1°, so a 179° angle and a 1° angle side by side make a straight line.
179° is 179/360 of a full circle, or 179π/180 radians. If you face north and turn 179° clockwise, you end up facing between SSE and S (closest to south (S)).
179° angle facts
| Angle type | Obtuse angle (between 90° and 180°) |
|---|---|
| Supplement (adds to 180°) | 1° |
| Explement (adds to 360°) | 181° |
| Radians | 179π/180 ≈ 3.124139 |
| Gradians | 198.8889 grad |
| Fraction of a turn | 179/360 (49.72%) |
| Degrees, minutes, seconds | 179° 0′ 0″ |
| Compass bearing | between SSE and S (closest to south (S)) |
Trigonometric values of 179°
| Function | Value |
|---|---|
| sin 179° | 0.017452 |
| cos 179° | −0.999848 |
| tan 179° | −0.017455 |
179° on a protractor
How to draw a 179° 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 179° 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 179°.
Drawing it a 179° angle without a protractor (rise and run method)
- 179° = 180° − 1°. Draw a straight line, pick a vertex on it, and build a 1° angle on one side as follows; the angle on the other side of the new line is 179°.
- 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 0.17 inches (about 3/16″) up that line and make a mark.
- Join the mark to the vertex. The angle at the vertex is 1°, because tan 1° ≈ 0.0175.
Where you see 179° angles
- The Earth turns 179° on its axis in about 11 h 56 min.
- Obtuse angles like 179° appear in reclining chair backs, open laptop screens, fan blades, and the corners of many-sided polygons.
Related angles
179° angle FAQ
What type of angle is 179°?
A 179° angle is an obtuse angle, because it is between 90° and 180°.
What is the supplement of 179°?
The supplement of 179° is 1°, because 179° + 1° = 180°. A 179° angle has no complement, because it is already larger than 90°.
How many radians is 179 degrees?
179° = 179π/180 radians ≈ 3.1241 rad. To convert degrees to radians, multiply by π/180: 179 × π/180 = 179π/180.
How do I measure a 179° angle on my screen?
Open the online protractor with 179° preset, or type 179 into its "Type an angle" box. You can then drag the arms onto your own lines to compare.
