
What is the supplementary angle of 20 degrees? Here we will define the supplementary angle of 20 degrees, show you how to calculate the supplementary angle of 20 degrees, and even illustrate the supplementary angle of 20 degrees (20°) so you have a solid understanding of what it means.
The supplementary angle of 20 degrees, also known as the supplement angle of 20 degrees, is the angle that when added to 20 results in a sum of 180. Therefore, to calculate the supplement angle of 20 degrees, we subtract 20 from 180. Here is the formula, the math, and the answer:
180 - angle = supplement angle
180 - 20 = 160
160 degrees
20 degrees plus the supplementary angle of 20 degrees equals 180 degrees, which means that together they will make a straight line.
The illustration below shows 20 degrees colored in red and the supplementary angle of 20 degrees, which is 160 degrees, colored in green.

As you can see from the illustration above, 20 degrees and 160 degrees form a straight line together. This proves that the two angles, 20 degrees and 160 degrees, are supplementary angles.
Supplementary Angle Calculator
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Supplementary angle of 20.1 degrees
Here is another trigonometry math problem that we have illustrated and calculated the answer to.