Question

Is a supplement of a acute angle always obtuse? What if one angle is 30 and the other is 170?

Answer 1

Yes because if an acute angle is less than 90, then its supplement (the angle that when added to another angle equals to 180°) has to be greater than 90° but less than 180° ( which is basically the definition of an obtuse angle)

A 30° angle is an acute angle and a 170° angle is obtuse but they are not supplementary angles because they do not add up to 180°

I hope this helps you :)