Polygon Investigation
YEAR 8 MATHEMATICS TOPIC: GEOMETRY
Directed Investigation – Diagonals in a Polygon
NAME: CALLIE VO DUE DATE: 9th November
WEIGHTING: 10%
Achievement Level
Criteria 0 1 2 3 4 5
Mathematical skills &
understanding (without ET)
Mathematical skills &
understanding (with ET)
Understanding and
interpretation of results and
information
Communication of
mathematical information
Organisation & presentation
Ability to work independently
Ability to work cooperatively
GRADE & COMMENT:
Diagonals in a Polygon
, Polygon Investigation
Introduction:
A polygon is a closed two-dimensional shape. It is a simple curve that is made up of straight-line
segments. It usually has three sides and three corners or more.
The word polygon comes from two Greek words. 'Poly' means 'many' and 'gon' means 'angles.'
The sum of exterior angles of a polygon will always be equal to 360 degrees, irrespective of the
number of sides it has.
In geometry, a vertex, often denoted by letters such as S, P, Q, R, is a point where two or more
curves, lines, or edges meet, each angular point of a polygon, polyhedron, or other figure. So how
many vertices are there in a polygon? It’s depended on how many angle the polygon has. For
example, a hexagon has six angles, so there are six vertices.
In geometry, a diagonal is a line segment joining two vertices of a polygon or polyhedron, when those
vertices are not on the same edge. But not all polygons have diagonals, like the triangles.
Some different type of polygon:
Hexagon:
A polygon with six straight sides and
angles.
Octagon:
A polygon with eight straight sides and
angles.
Triangle:
A polygon with three straight sides and
angles.
Pentagon: A polygon with five straight
sides and angles.
Mathematical Investigation and Analysis
1. -There are six vertices in this polygon.
2. – There are nine diagonals.
3. Consider the table below.
Number of
Maximum Number of Vertices x
Number of
Number of Diagonals from Number of
Vertices
Diagonals each Vertex Diagonals from
each Vertex
(n)
(d) (v)
nxv
YEAR 8 MATHEMATICS TOPIC: GEOMETRY
Directed Investigation – Diagonals in a Polygon
NAME: CALLIE VO DUE DATE: 9th November
WEIGHTING: 10%
Achievement Level
Criteria 0 1 2 3 4 5
Mathematical skills &
understanding (without ET)
Mathematical skills &
understanding (with ET)
Understanding and
interpretation of results and
information
Communication of
mathematical information
Organisation & presentation
Ability to work independently
Ability to work cooperatively
GRADE & COMMENT:
Diagonals in a Polygon
, Polygon Investigation
Introduction:
A polygon is a closed two-dimensional shape. It is a simple curve that is made up of straight-line
segments. It usually has three sides and three corners or more.
The word polygon comes from two Greek words. 'Poly' means 'many' and 'gon' means 'angles.'
The sum of exterior angles of a polygon will always be equal to 360 degrees, irrespective of the
number of sides it has.
In geometry, a vertex, often denoted by letters such as S, P, Q, R, is a point where two or more
curves, lines, or edges meet, each angular point of a polygon, polyhedron, or other figure. So how
many vertices are there in a polygon? It’s depended on how many angle the polygon has. For
example, a hexagon has six angles, so there are six vertices.
In geometry, a diagonal is a line segment joining two vertices of a polygon or polyhedron, when those
vertices are not on the same edge. But not all polygons have diagonals, like the triangles.
Some different type of polygon:
Hexagon:
A polygon with six straight sides and
angles.
Octagon:
A polygon with eight straight sides and
angles.
Triangle:
A polygon with three straight sides and
angles.
Pentagon: A polygon with five straight
sides and angles.
Mathematical Investigation and Analysis
1. -There are six vertices in this polygon.
2. – There are nine diagonals.
3. Consider the table below.
Number of
Maximum Number of Vertices x
Number of
Number of Diagonals from Number of
Vertices
Diagonals each Vertex Diagonals from
each Vertex
(n)
(d) (v)
nxv
