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2. Types of Angle Acute angles 1 2 3 Acute angles are angles less than 90 o

3. 90 o on a protractor Types of Angle Right angles A right angle is an angle of 90 o Vertical Horizontal A right angle will occur when a horizontal line and a vertical line meet. Horizontal Vertical Horizontal Vertical 1 2 3 If the angle between two lines is a right angle then the lines are perpendicular to each other.

4. Vertical Horizontal Types of Angle Right angles Perpendicular lines

5. Which simple shapes contain right-angles?

6. Can Pentagons, Hexagons and Octagons have right-angles? Regular PentagonRegular Hexagon Regular Octagon Irregular Pentagon Irregular Hexagon Irregular Octagon 6 six 5 five 8 Eight

7. Types of Angle Obtuse angles 1 2 3 Obtuse angles are greater than 90 o but less 180 o

8. What types of angle can you see in the shapes below? Regular PentagonRegular Hexagon Regular Octagon Irregular Pentagon Irregular Hexagon Irregular Octagon 6 six 5 five 8 Eight

9. Types of Angle Straight angles 180 o on a protractor A straight angle is an angle of 180 o

10. Types of Angle Reflex angles Reflex angles are greater than 180 o but less than 360 o 1 23 4

11. 1 2 3 4 56 7 8 9 Acute Obtuse Acute Reflex Right Obtuse Acute Reflex Obtuse