In this lesson students explore and use the properties of isosceles triangles to solve real world problems. After learning the basics of isosceles triangles they apply what they learn to the structure of the Eiffel Tower.

A video introduces the topic of isosceles triangles, along with two isosceles triangle theorems. Students are shown how to find the values for the isosceles pair, given the third angle, by solving a multi-step equation.

Students then apply what they have learned about isosceles triangles by learning about the triangular trusses in the Eiffel Tower. Students learn about what a truss is, what their function is in a building, and why isosceles triangle trusses are an effective form of a truss. Students then learn about two important properties of isosceles triangles involve the perpendicular bisector of the base and the angle bisector of the third angle. Another video ties together triangular trusses, perpendicular bisectors, and angle bisectors.

Students then complete a cloze assessment, in which they identify key words that are missing from a reading passage. 

This module can be used as an introductory lesson on isosceles triangles in a middle school geometry unit. The content aligns with grade 7 Core State Standards, but this module can be used as a refresher for higher grades.

This module can be assigned to individual students or groups of students. Students should be able to complete this lesson in 20 minutes.

In this module students explore indirect measurement by seeing how simple angle measure, height measurements, and tangent ratios can be used to calculate distances. The context of castles provides a historically relevant military purpose for the tallness of castles.

This module explores Himeji Castle in Japan, as well as other castles. Some of the concepts explored in this module include:

• Angle measurements and alternate interior angles of parallel lines
• Tangent ratios
• Linear functions, in particular the functional relationship between a castle's height and its line of sight for a given angle

This module provides a nice blend of algebra and geometry topics and can be used in an algebra unit on linear functions, a geometry unit on tangent ratios, or even a pre-calculus lesson on tangent ratios and functions.

Definition of the term "Adjacent Angles."

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The definition of the term "Supplementary Angles."

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The definition of the term "Vertical Angles."

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This piece of clip art consists of: Adjacent Angles--Labeled. Note: The download is a JPG file.

This piece of clip art consists of: Adjacent Angles--Unlabeled. Note: The download is a JPG file.

This piece of clip art consists of: Complementary Angles--Labeled.  Note: The download is a JPG file.

This piece of clip art consists of: Complementary Angles--Unlabeled.  Note: The download is a JPG file.

This piece of clip art consists of: Supplementary Angles--Labeled. Note: The download is a JPG file.

This piece of clip art consists of: Supplementary Angles--Unlabeled. Note: The download is a JPG file.

This piece of clip art consists of: Vertical Angles--Labeled. Note: The download is a JPG file.

This piece of clip art consists of: Vertical Angles--Unlabeled. Note: The download is a JPG file.

Quadrilateral Classification: Example 1. A generic quadrilateral with all side measures shown numerically.

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Quadrilateral Classification: Example 2. A generic quadrilateral with all side measures shown as variables.

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Quadrilateral Classification: Example 3. A generic quadrilateral with all angle measures shown numerically.

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Quadrilateral Classification: Example 4. A generic quadrilateral with all angle measures shown as variables.

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Quadrilateral Classification: Example 5. A generic quadrilateral with angle measures shown as numbers and variables.

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Quadrilateral Classification: Example 6. A rectangle with all side measures shown numerically.

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Quadrilateral Classification: Example 7. A rectangle with all side measures shown as variables.

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Quadrilateral Classification: Example 8. A rectangle with all side measures shown as numbers and variables.

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Quadrilateral Classification: Example 9. A rectangle with all angle measures shown numerically.

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Quadrilateral Classification: Example 10. A rectangle with all angle measures shown as numbers and variables.

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Quadrilateral Classification: Example 11. A square with all angle measures shown numerically.

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Quadrilateral Classification: Example 12. A square with all angle measures shown as variables.

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To see the complete collection of Math Examples on this topic, click on this link: https://bit.ly/3e5VsCx