The sides of the angles The vertex B C A Side ABSide AC

The sides of the angles

The vertex

BC

A

Side ABSide AC

(1) Name of the angle<BAC or < CAB or <A

(2) Vertex of the angleRemember that any angle have only one vertexAnd in this angle the vertex is A

(3) Sides of the angle

AB and ACAnd remember that the side all the time is ray

In any angle you must to know:

Types of Angle

Acute angles

1 2 3

Acute angles are angles less than 90o

Acute angles

Baby Acute Angle

This is baby Acute angle. Isn’t he cute?! He loves a hug,He’s the smallest of the family, measuring less than 90°.

90o on a protractor

Types of AngleRight angles

A right angle is an angle of 90o

1 2 3

Right angles

Mrs. Right Angle

This is me. I’m Mrs. Right Angle.I always measure 90°, my favourite shape is a square, my husband tells you, I’m always right!

Types of Angle

Obtuse angles

1 2 3

Obtuse angles are greater than 90o but less 180o

Obtuse angles

Mr. Obtuse AngleThis is Obtuse. He’s the husband of the family. He’s bigger than Right and Acute ., and he always measures between 90° and 180° (depending on how much dinner he’s eaten!)

Types of Angle

Straight angles

180o on a protractor180o on a

protractor

A straight angle is an angle of 180o

Straight angles

Acute Obtuse Acute

Right

Obtuse

Acute Obtuse

SummeryAcute angles

Less than 90 °

Right angles

All the time Equal 90 °

Obtuse angles

Greater 90 ° and less than

180 °

Straight angles

All the time equal 180 °