Complementary angles add to 90 degrees. Supplementary angles add to 180 degrees. They do not have to be adjacent. Angle facts as a set are in lines and angles.
90 or 180
A 35-degree angle and a 55-degree angle are complementary. A 110-degree angle and a 70-degree angle are supplementary. Two angles on a straight line are supplementary even if the word never appears.
Corresponding and alternate interior angles show up when a transversal cuts parallels, in corresponding and alternate interior angles. Triangle interiors still add to 180, in triangle angle sum. The short list is in ACT Math formulas.
The bottom line
Complement: 90. Supplement: 180. Adjacent or not, the sum is the job.
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