Download Compare and Contrast Polygons Unit 4, Lesson 3

Warm Up
• Brooks and Jackson were constructing
quadrilaterals (squares, rhombi, rectangles,
parallelograms, trapezoids) on drawing paper
and decided to include diagonals in each of
their shapes. After they were finished their
mom asked them to color the shapes that had
diagonals that were all congruent to each
other. Which polygons should the boys have
colored?
Constructing Polygons
Alignment Lesson
Perpendicular lines
intersect or meet to
form right angles
Parallel lines
always are the same
distance apart and
never touch
Equilateral
triangle
An equilateral triangle has
all congruent sides
Isosceles
triangle
An isosceles triangle has all
at least two congruent sides
What are ways to classify triangles?
Scalene
Classify by the
length of their
sides
Isosceles
Equilateral
Triangles
Acute
Classify by the
measure of the
angles
Right
Obtuse
Vocabulary Review
• Quadrilateral - a polygon with four sides
Vocabulary Review
• Parallelogram - a polygon with two pairs of
parallel sides
• A rectangle is a parallelogram
• A rhombus is a parallelogram
• A square is a parallelogram
Vocabulary Review
• Square - a parallelogram with all sides the
same length and all right angles
– Diagonals are congruent
– Diagonals are perpendicular
– A quadrilateral
Vocabulary Review
• Rectangle - a parallelogram with all right
angles
– Diagonals are congruent
– Opposite sides are congruent
Vocabulary Review
• Rhombus - a parallelogram with all sides the
same length
• Diagonals are NOT congruent
• Diagonals are perpendicular
Vocabulary Review
• Trapezoid – a quadrilateral with ONLY one pair
of parallel sides
• Right trapezoid - a trapezoid with right angles
Vocabulary Review
• Pentagon - a polygon with five sides
Vocabulary Review
• Hexagon - a polygon with six sides
Vocabulary Review
• Octagon – a polygon with eight sides
Vocabulary Review
• Kite - A quadrilateral with two distinct pairs of
congruent, adjacent sides and diagonals that
intersect at a right angle.
Geoboards (interactive geoboard)
• Construct a polygon that has “3 sides with 2 sides equal” on
your geoboards
• What is the correct geometry term to describe our triangles?
• Find Day 43, “Constructing Polygons Set A” (pages 1 and 2).
• Find Day 43, “Geoboard Paper”
• Independently create each polygon.
• After creating, draw each polygon on “Geoboard Paper,” and
compare your shape with your partner’s and record
similarities and differences between the two shapes they
constructed.
• Lastly, record a name for the polygon they have drawn.
Geoboards
• Math Talk!! Let’s discuss the
polygons you constructed.
• Now let’s try “Constructing
Polygons Set B”
Homework
Day 43, “Constructing
Polygons Homework”