Lesson 11
Polygons
Let’s investigate polygons and their areas.
Problem 1
Select all the polygons.
![Six figures labeled A, B, C, D, E, F.](https://cms-im.s3.amazonaws.com/zwbWtpTZeaa4mFmd8mjcGr1v?response-content-disposition=inline%3B%20filename%3D%226-6.1.D.PP_Image_1.png%22%3B%20filename%2A%3DUTF-8%27%276-6.1.D.PP_Image_1.png&response-content-type=image%2Fpng&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=AKIAXQCCIHWF3XOEFOW4%2F20240727%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Date=20240727T042332Z&X-Amz-Expires=604800&X-Amz-SignedHeaders=host&X-Amz-Signature=acf045e1d044f33c5ec70658fd05948c09f4847dfb138ef9124d42c11efd169d)
A
B
C
D
E
F
Problem 2
Mark each vertex with a large dot. How many edges and vertices does this polygon have?
![12 sided polygon resembling a star](https://cms-im.s3.amazonaws.com/LD3y7y9YwqxkdKrPQXJWQXff?response-content-disposition=inline%3B%20filename%3D%226-6.1.D.PP_Image_2.1.png%22%3B%20filename%2A%3DUTF-8%27%276-6.1.D.PP_Image_2.1.png&response-content-type=image%2Fpng&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=AKIAXQCCIHWF3XOEFOW4%2F20240727%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Date=20240727T042333Z&X-Amz-Expires=604800&X-Amz-SignedHeaders=host&X-Amz-Signature=e9499383a07285ea577b8c1aa414b3e673c79feb79822f9691d0a6de27668be3)
Problem 3
Find the area of this trapezoid. Explain or show your strategy.
![Trapezoid, bases 8 and 4 units. Height 3 units.](https://cms-im.s3.amazonaws.com/avt3EEccdUpiJ2xz7Gduju2X?response-content-disposition=inline%3B%20filename%3D%226-6.1.D.PP_Image_4.png%22%3B%20filename%2A%3DUTF-8%27%276-6.1.D.PP_Image_4.png&response-content-type=image%2Fpng&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=AKIAXQCCIHWF3XOEFOW4%2F20240727%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Date=20240727T042333Z&X-Amz-Expires=604800&X-Amz-SignedHeaders=host&X-Amz-Signature=935bd3b2b67c6e020ad3c301b80f246a61121886ee5ee1db2f8f1f6f0c89e6e2)
Problem 4
Lin and Andre used different methods to find the area of a regular hexagon with 6-inch sides. Lin decomposed the hexagon into six identical, equilateral triangles. Andre decomposed the hexagon into a rectangle and two triangles.
![2 identical hexagons labeled Lin’s method and Andre’s method.](https://cms-im.s3.amazonaws.com/zS6MDGFZ6zDKUinTZDYPAZFE?response-content-disposition=inline%3B%20filename%3D%226-6.1.C.PP.New.Image.17-18.png%22%3B%20filename%2A%3DUTF-8%27%276-6.1.C.PP.New.Image.17-18.png&response-content-type=image%2Fpng&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=AKIAXQCCIHWF3XOEFOW4%2F20240727%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Date=20240727T042333Z&X-Amz-Expires=604800&X-Amz-SignedHeaders=host&X-Amz-Signature=555285b5d565f3cc7ef9220bba2b2bd2cf32cb5a5137f6aa9f76940c42e55459)
Find the area of the hexagon using each person’s method. Show your reasoning.
Problem 5
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Identify a base and a corresponding height that can be used to find the area of this triangle. Label the base \(b\) and the corresponding height \(h\).
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Find the area of the triangle. Show your reasoning.
Problem 6
On the grid, draw three different triangles with an area of 8 square units. Label the base and height of each triangle.
![A blank coordinate plane with 16 evenly spaced horizontal units and 12 evenly spaced vertical units.](https://cms-im.s3.amazonaws.com/Mtje8WXsjQDE9fQ8VtAvNX1D?response-content-disposition=inline%3B%20filename%3D%226-6.7.C.PP.Image.00.Blank-Grid.png%22%3B%20filename%2A%3DUTF-8%27%276-6.7.C.PP.Image.00.Blank-Grid.png&response-content-type=image%2Fpng&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=AKIAXQCCIHWF3XOEFOW4%2F20240727%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Date=20240727T042333Z&X-Amz-Expires=604800&X-Amz-SignedHeaders=host&X-Amz-Signature=997fbea251c09a9d1cc9b92affca5ccb422202bd03e26e8b2dbf11df47545d03)