A 143° angle is obtuse because it is greater than 90° and less than 180°. Its supplement is 37°, so a 143° angle and a 37° angle side by side make a straight line.
143° is 143/360 of a full circle, or 143π/180 radians. If you face north and turn 143° clockwise, you end up facing between SE and SSE (closest to southeast (SE)).
143° angle facts
| Angle type | Obtuse angle (between 90° and 180°) |
|---|---|
| Supplement (adds to 180°) | 37° |
| Explement (adds to 360°) | 217° |
| Radians | 143π/180 ≈ 2.495821 |
| Gradians | 158.8889 grad |
| Fraction of a turn | 143/360 (39.72%) |
| Degrees, minutes, seconds | 143° 0′ 0″ |
| Compass bearing | between SE and SSE (closest to southeast (SE)) |
Trigonometric values of 143°
| Function | Value |
|---|---|
| sin 143° | 0.601815 |
| cos 143° | −0.798636 |
| tan 143° | −0.753554 |
143° on a protractor
How to draw a 143° 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 143° 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 143°.
Drawing it a 143° angle without a protractor (rise and run method)
- 143° = 180° − 37°. Draw a straight line, pick a vertex on it, and build a 37° angle on one side as follows; the angle on the other side of the new line is 143°.
- 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 7.54 inches (about 7 9/16″) up that line and make a mark.
- Join the mark to the vertex. The angle at the vertex is 37°, because tan 37° ≈ 0.7536.
Where you see 143° angles
- The Earth turns 143° on its axis in about 9 h 32 min.
- Obtuse angles like 143° appear in reclining chair backs, open laptop screens, fan blades, and the corners of many-sided polygons.
Related angles
143° angle FAQ
What type of angle is 143°?
A 143° angle is an obtuse angle, because it is between 90° and 180°.
What is the supplement of 143°?
The supplement of 143° is 37°, because 143° + 37° = 180°. A 143° angle has no complement, because it is already larger than 90°.
How many radians is 143 degrees?
143° = 143π/180 radians ≈ 2.4958 rad. To convert degrees to radians, multiply by π/180: 143 × π/180 = 143π/180.
How do I measure a 143° angle on my screen?
Open the online protractor with 143° preset, or type 143 into its "Type an angle" box. You can then drag the arms onto your own lines to compare.
