## Presentation on theme: "All about Shapes."— Presentation transcript:

Properties of Shapes Number of sides Number of angles
Number of lines of symmetry Regular or irregular Right Angles Parallel lines

Shapes Triangles Quadrilaterals Polygons Regular Shapes Key Words

What shape is this?

A Square

How many lines of symmetry does a square have?
2 1 3 4

Properties of a Square Has 4 equal sides Has 4 equal angles
Each angle is a right angle Has 4 lines of symmetry Is a regular shape

What shape is this?

A Rectangle

How many lines of symmetry does a rectangle have?
1 2

Properties of a Rectangle
Has 2 pairs of equal sides Has 4 equal angles Each angle is a right angle Has 2 lines of symmetry Is an irregular shape

What shape is this?

A Parallelogram

How many lines of symmetry does a parallelogram have?
None!

Properties of a Parallelogram
Has 2 pairs of equal sides Has 2 pairs of equal angles Opposite sides are parallel Has NO lines of symmetry Is an irregular shape

What shape is this?

A Rhombus

How many lines of symmetry does a rhombus have?
1 2

Properties of a Rhombus
Has 4 equal sides Has 2 pairs of equal angles Opposite sides are parallel Has 2 lines of symmetry Is an irregular shape

What shape is this?

A Trapezoid

How many lines of symmetry does a trapezoid have?
None!

How many lines of symmetry does this trapezoid have ?
1 Because these angles are equal.

Properties of a Trapezoid
Has unequal sides One pair of opposite sides are parallel Usually has NO lines of symmetry Is an irregular shape

What shape is this?

A diamond

How many lines of symmetry does a diamond have?
1

Properties of a diamond
Has 2 pairs of equal sides Has 1 pair of equal angles Equal sides are adjacent Has 1 line of symmetry Is an irregular shape

Triangles Shapes with 3 sides!

What type of triangle is this?

An Equilateral Triangle

How many lines of symmetry does an equilateral triangle have?
1 2 3

Properties of an Equilateral Triangle
Has 3 equal sides Has 3 equal angles Each angle is a 60o angle Has 3 lines of symmetry Is a regular shape

What type of triangle is this?

An Isosceles Triangle

How many lines of symmetry does an Isosceles Triangle have?
1

Properties of an Isosceles Triangle
Has 2 equal sides Has 2 equal angles Has 1 line of symmetry Is an irregular shape

What type of triangle is this?

A Scalene Triangle

How many lines of symmetry does a scalene triangle have?
None!

Properties of an Scalene Triangle
Has NO equal sides Has NO equal angles Has NO lines of symmetry Is an irregular shape

What type of triangle is this?

A right triangle

Properties of a right triangle
Has 1 right angle May be an isosceles triangle May have 1 line of symmetry Is an irregular shape It will be isosceles and have 1 line of symmetry when these 2 sides are equal.

Triangles Shapes with 3 sides!

Key Words Regular Shape Parallel Perpendicular Vertex Diagonal Bisect

Regular Shape Shapes are regular when
All their sides are the same length All their angles are the same size

when they are always the same distance apart.
Parallel Lines are parallel when they are always the same distance apart.

when they meet at right angles.
Perpendicular Lines are perpendicular when they meet at right angles.

Vertex A Vertex is a corner of a shape where two lines meet.

Diagonal A Diagonal is a straight line that joins one corner (vertex) of a shape to a non adjacent corner (vertex)

Bisect A line that cuts a shape exactly in half, Bisects the shape

Key Words Regular Shape Parallel Perpendicular Vertex Diagonal Bisect

Polygons Shapes with many sides!

What shape is this?

A Hexagon

How many lines of symmetry does a hexagon have?
4 1 2 5 6 3

Properties of a Regular Hexagon
Has 6 equal sides Has 6 equal angles Has 6 lines of symmetry

What shape is this?

A Pentagon

How many lines of symmetry does a pentagon have?
1 3 4 5 2

Properties of a Regular Pentagon
Has 5 equal sides Has 5 equal angles Has 5 lines of symmetry

Polygons Shapes with many sides!

Lines of Symmetry - Look at these shapes
Can you suggest a rule?

Regular shapes All the sides are the same length
All the angles are equal Have the same number of lines of symmetry as the number of sides

How many lines of symmetry?
Look at these shapes Heptagon Octagon How many lines of symmetry?

Lines of symmetry Heptagon Octagon 7 8

Lines of symmetry Heptagon Octagon 7 8