6. 6
Shape Name Number of sides
Triangle 3
Quadrilateral 4
Pentagon 5
Hexagon 6
Septigon 7
Octagon 8
Nanagon 9
Decagon 10
7. A quadrilateral is a
two-dimensional
figure formed by
connecting four
segments endpoint
to endpoint with each
segment intersecting
exactly two others
More
examples
9. “Quad” means four. Why would all of these
shapes be called “quadrilaterals”?
Each shape has four sides.
square
parallelogram
rhombus
rectangle
trapezoid
10. We can identify the
quadrilateral by :
their angles
and the length of
their sides.
11. Square
A square has four sides that are each the same length.
It also has four right angles (perfect corners).
1
2 3
4
12. A rhombus has four sides that are each
the same length.
But it has two acute and two obtuse
angles.
acute
acuteobtuse
obtuse
13. Square and Rhombus
• A square and a rhombus both have four
sides that are the same length. So, how are
they different?
14. SQUARE AND RHOMBUS
A rhombus can be thought of as a
slanted square.
If we push on the left-hand side of this
square, it might end up looking like…
The only difference between a square
and a rhombus is their angles.
a rhombus
15. Trapezoid
• A trapezoid has four sides.
• Two sides are parallel.
• The opposing two sides are not parallel.
Those are
parallel.
Those are
not
parallel.
16. Rectangle
•A rectangle has four
sides – two long sides
and two short sides.
•Two sides are parallel.
•The opposing two sides
are also parallel.
•It also has four right
angles.
17. Parallelogram
•A parallelogram has
four sides – two long
sides and two short
sides.
•Two sides are parallel.
•The opposing two
sides are also parallel.
•But, it has two acute
and two obtuse angles.
18. A parallelogram can be thought of as
a slanted rectangle.
If we push on the left-hand side of this
rectangle, it might end up looking
like…
a parallelogram
19.
20. SHAPE SIDES ANGLES PARALLEL
LINES
Square 4 same
length
4 right angles 2 sets
Rhombus 4 same
length
2 acute
2 obtuse
2 sets
Trapezoid different
lengths
different
angles
1 set
Rectangle 2 long,
2 short
4 right angles 2 sets
Parallelogram 2 long,
2 short
2 acute
2 obtuse
2 sets
21. 22
Quadrilateral Only 1
Pair of
Parallel
Sides
2 Pairs
of
Parallel
sides
All sides
must be
congruent
Opposite
sides are
congruent
All angles
must be
right
angles
SQUARE
RECTANGLE
RHOMBUS
PARALLELOGRAM
TRAPEZOID