Question

राइट फाइव नेम्स एंड count
द नंबर ऑफ एंगल्स ऑफ each टाइप्स राइट एंगल acute angle obtuse angle
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Answer 1

Answer:

Names of Angles

As the Angle Increases, the Name Changes:

types of angle

Type of Angle Description

Acute Angle is less than 90°

Right Angle is 90° exactly

Obtuse Angle is greater than 90° but

less than 180°

Straight Angle is 180° exactly

Reflex Angle is greater than 180°

Full Rotation is 360° exactly

Try It Yourself:

Circle

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In One Diagram

This diagram might make it easier to remember:

Also: Acute, Obtuse and Reflex are in alphabetical order.

angle types together

acute

Also: the letter "A" has an acute angle.

Be Careful What You Measure

angle obtuse vs reflex

The smaller angle is an Obtuse Angle,

but the larger angle is a Reflex Angle

So when naming the angles make sure that you know which angle is being asked for!

Positive and Negative Angles

When measuring from a line:

a positive angle goes counterclockwise (opposite direction that clocks go)

a negative angle goes clockwise

positive negative angle

Example: −67°

negative 67 degrees

angle

Parts of an Angle

The corner point of an angle is called the vertex

And the two straight sides are called arms

The angle is the amount of turn between each arm.

How to Label Angles

angles

There are two main ways to label angles:

1. give the angle a name, usually a lower-case letter like a or b, or sometimes a Greek letter like α (alpha) or θ (theta)

2. or by the three letters on the shape that define the angle, with the middle letter being where the angle actually is (its vertex).

Example angle "a" is "BAC", and angle "θ" is "BCD"