All the solutions provided in McGraw Hill My Math Grade 3 Answer Key PDF Chapter 14 Lesson 2 Polygons will give you a clear idea of the concepts.
McGraw-Hill My Math Grade 3 Answer Key Chapter 14 Lesson 2 Polygons
A polygon is a closed two-dimensional figure formed by three or more straight sides that do not cross each other.
You can classify polygons using one or more of the following attributes. An attribute is a characteristic of a figure.
- number of sides
- number of angles
Math in My World
Example 1
Look at the soccer ball. The blue shape outlined in white is a polygon. Describe and classify the polygon by its attributes.
A pentagon is a polygon with 5 sides and 5 angles.
The blue shape outlined in white has _____________ sides and _____________ angles.
So, the shape is a pentagon.
Answer:
The blue shape outlined in white has 5 sides and 5 angles.
So, the shape is a pentagon.
Example 2
The road sign shown is a polygon. Describe and classify the polygon by its attributes.
An octagon is a polygon with 8 sides and 8 angles.
The road sign has _______________ sides and ______________ angles.
So, the sign is an octagon.
Answer:
The road sign has 8 sides and 8 angles.
So, the sign is an octagon.
Talk Math
What attributes do the shapes in the Key Concept box have in common?
Answer:
The sides and angles attributes to the shapes in the Key Concept to have in common.
Guided Practice
Question 1.
Describe the shape of the sign below. Determine the number of sides and angles. Then classify the shape.
The polygon has ______________ sides and ____________ angles.
So, the sign is a(n) _______________.
Answer:
The polygon has 3 sides and 3 angles.
So, the sign is a(n) triangle.
Independent Practice
Question 2.
______________ sides
______________ angles
This is a(n) ______________.
Answer:
Given that the shape is octagon.
It has 8 sides.
Tt has 8 angles.
This is a(n) octagon.
Question 3.
______________ sides
______________ angles
This is a(n) ______________.
Answer:
The given shape is pentagon.
It has 5 sides.
It has 5 angles.
This is a(n) pentagon.
Question 4.
______________ sides
______________ angles
This is a(n) ______________.
Answer:
Given that the shape is hexagon.
It has 6 sides.
It has 6 angles.
This is a(n) hexagon.
Question 5.
______________ sides
______________ angles
This is a(n) ______________.
Answer:
Given that the shape is a triangle.
It has 3 sides.
It has 3 angles.
This is a(n) triangle.
Question 6.
______________ sides
______________ angles
This is a(n) ______________.
Answer:
Given that the shape is rectangle.
It has 4 sides.
It has 4 angles.
This is a(n) rectangle.
Question 7.
______________ sides
______________ angles
This is a(n) ______________.
Answer:
Given that the shape is square.
It has 4 sides.
It has 4 angles.
This is a(n) square.
Draw an example of each polygon.
Question 8.
triangle
Answer:
The triangle has 3 sides and 3 angles.
Question 9.
quadrilateral
Answer:
The quadrilateral has 4 sides and 4 angles.
Problem Solving
Question 10.
Bryson pushed a square pattern block and a triangular pattern block together as shown. What new polygon did he create?
Answer:
Given that,
Bryson pushed a square pattern block and a triangular pattern block together then it form has a pentagon.
The new polygon is pentagon.
Question 11.
Classify the polygon that has fewer angles than a quadrilateral.
Answer:
The triangle has 3 sides and 3 angles. And it is polygon.
The quadrilateral has 4 sides and 4 angles. And it is also called has polygon.
The triangle has fewer angles than a quadrilateral.
Question 12.
Mathematical PRACTICE Explain to a Friend Explain why each figure below is not a polygon.
Answer:
The given figures are not a polygon. Because the shapes has curved sides and the shape is not fully enclosed.
HOT Problems
Question 13.
Mathematical PRACTICE Keep Trying Draw an example of a figure that is not a polygon. Explain.
Answer:
The circle is not a polygon. Because it is curved shape and it does not have sides and angles.
Question 14.
Mathematical PRACTICE Identify Structure Draw and classify a polygon that has 4 sides with 2 angles that are greater than right angles.
Answer:
The polygon that has 4 sides with 2 angles that are greater than right angles is a quadrilateral.
Question 15.
Building on the Essential Question How do I classify polygons using their attributes?
Answer:
We can classify the polygons using regular and irregular attributes.
Regular means equal side lengths and same angles.
Irregular means non equal sides and non equal angles.
McGraw Hill My Math Grade 3 Chapter 14 Lesson 2 My Homework Answer Key
Practice
Describe each shape. Determine the number of sides and angles. Then classify each shape.
Question 1.
_____________ sides
_____________ angles
This is a(n) _____________.
Answer:
Given that the shape is hexagon.
It has 6 sides.
It has 6 angles.
This is a(n) hexagon.
Question 2.
_____________ sides
_____________ angles
This is a(n) _____________.
Answer:
Given that the shape is triangle.
It has 3 sides
It has 3 angles.
This is a(n) triangle.
Question 3.
Mathematical PRACTICE Identify Structure Classify the polygons that are used to create the figure shown.
Answer:
The polygons that are used to create the figure shown are triangle, hexagon and quadrilateral.
Problem Solving
Question 4.
What is another name for a square, other than polygon?
Answer:
The another name for a square other than polygon is quadrilateral.
The quadrilateral has 4 sides and it is a four sided polygon.
Question 5.
Mathematical PRACTICE Use Math Tools Draw and label the polygon you would get when you fold the hexagon shown, in half along the dotted line.
Answer:
The given figure is hexagon.
When the hexagon is folded then it form has a quadrilateral or trapezoid.
Question 6.
Is the figure shown to the right a polygon? Explain.
Answer:
The given figure is not a polygon because it has no straight lines.
Vocabulary Check
Choose the correct word to complete each sentence.
hexagon
polygon
quadrilateral
Question 7.
A ______________ is a closed two-dimensional figure formed of three or more straight sides that do not cross each other.
Answer:
A polygon is a closed two-dimensional figure formed of three or more straight sides that do not cross each other.
Question 8.
A ______________ is a polygon with 6 sides and 6 angles.
Answer:
A hexagon is a polygon with 6 sides and 6 angles.
Question 9.
A _____________ is a polygon with 4 sides and 4 angles.
Answer:
A quadrilateral is a polygon with 4 sides and 4 angles.
Test Practice
Question 10.
Which of the following figures is a hexagon?
Answer:
The hexagon has 6 sides.
The option C has 6 sides.
So, Option C is the correct answer.