There are two types of angles that are smaller than 180 degrees: acute and obtuse. Acute angles are those that are smaller than a right angle (90 degrees) and obtuse angles are those that are larger than a right angle but smaller than 180(ex: 100 degrees, 91 degrees, etc.) Obtuse and acute angles are easy to identify without actually using a protractor; they are usually exaggerated on tests and assignments. On top of that 180 degree angles are called straight.
less than than a 90 degree angle
A right angle is a measure of 90 degrees or a 1/4 of a turn
That is called an obtuse angle.
An angle above 90 but less than 180 degrees is an obtuse angle An angle above 180 degrees is a reflex angle
An angle greater than 90 degree is an obtuse angle.
Wasam
less than than a 90 degree angle
A 77 degree angle is an acute angle because it is greater than 0 but less than 90 degrees.
A right angle is a measure of 90 degrees or a 1/4 of a turn
an acute angle because it is less than ninety degrees.
An obtuse angle is an angle which is more than 90 degrees, but less than 180.
That is called an obtuse angle.
An angle greater than 90 degrees but less than 180 degrees in called an obtuse angle.
A reflex angle.
It is an obtuse angle because it is greater than 90 but less than 180 degrees
An angle above 90 but less than 180 degrees is an obtuse angle An angle above 180 degrees is a reflex angle
the complement of an acute angle (less than 90 degrees) is 90 minus the angle which is 71 degrees in this case.