Acute
What is an acute angle?
An angle between 0° and 90°
What is a right angle?
An angle exactly 90°
What is an obtuse angle?
An angle between 90° and 180°.
What is a straight angle?
An angle exactly 180°.
What is a reflex angle?
An angle between 180° and 360°.
Give a degree example of an acute angle.
Any degree between 0° and 90° (eg. 30°, 45°, or 60°)
What is the size of a right angle?
Exactly 90°.
What is the size range of obtuse angles?
Between 90° and 180°.
What is the size of a straight angle?
Exactly 180°.
What is the size range of reflex angles?
Between 180° and 360°.
What is the size range of acute angles?
Between 0° and 90°
Give a real-world example of a right angle.
Corners of a book, window, or paper.
Give an example of an obtuse angle.
120°, 135°, or 150°.
Give an example of a straight angle.
A flat line or a straight road.
Give an example of a reflex angle.
270°, 300°, or 350°.
Is 90° an acute angle?
No, 90° is a right angle
What symbol marks a right angle?
A small square at the vertex.
Can an obtuse angle be 90°?
No, 90° is a right angle.
Can a straight angle be a reflex?
No, reflex angles are bigger than 180°.
Is 360° a reflex angle?
No, 360° is a full revolution.
Name two examples of acute angles.
30° and 60° (or any two < 90°).
Is 45° a right angle?
No, it is an acute angle.
Compare obtuse and acute angles.
Obtuse > 90°, acute < 90°.
Is 180° a straight or reflex angle?
It is a straight angle.
What is the difference between reflex and obtuse angles?
Reflex is between 180° and 360°, obtuse between 90° and 180°.