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types of anGles

Angles are of different types.

1. Acute angle: An angle whose measure is less than 90° is A
called an acute angle.
In the figure, ∠ABC = 50°.

Thus, ∠ABC is an acute angle. 50°
B C
Acute angle

2. Right angle: An angle whose measure is 90° is called a X
right angle.
In the figure, ∠XYZ = 90°.

Thus, ∠XYZ is a right angle. 90°
Y Z
Right angle

3. Obtuse angle: An angle whose measure is more than P

90° and less than 180° is called an obtuse angle.
In the figure, ∠PQR = 120°.

Thus, ∠PQR is an obtuse angle. 120°
Q R
Obtuse angle

4. Straight angle: An angle which is 180° is called a straight 180°
angle.

In the figure, ∠COD = 180°. C O D
Thus, ∠COD is a straight angle. Straight angle

5. Reflex angle: An angle greater than 180° and less than 250°
360° is called a reflex angle. O K

Here, ∠ROK = 250°.
So, ∠ROK is a reflex angle.

R

Reflex angle
6. Complete angle: An angle whose measure is equal to 360° 360°

is called a complete angle. X
The adjacent angle measures 360°. Y Z

Thus, ∠XYZ is a complete angle. Complete angle

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