What kind of an angle is it, if it is greater than its supplement?

Angle, which can be drawn by using ruler and compass, should be multiple of $15°$.

To draw an angle of $90°$ using a ruler and compass, we bisect the angle between $60°$ and $120°$.

An angle has an interior as well as an exterior region.

Protractor is used to mark off equal lengths, but does not measure them, also used to draw arcs and circles.

Perpendicular lines are the lines that intersect at an angle $60°$.

The perpendicular bisector of a line segment is the line that is perpendicular to the line segment.

$30°, 60°, 120°, 90°, 45°$ etc. are some special angles which can be constructed without use of protractor.