7/27/2019 Lesson Plan Pythag Intro

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Lesson Planning S

Title:Pythagoras Theorem

Learning Objectives:

By the end of the lesson:

All students should be able to identify the hypotenuse of a right angled triangle as the longest side. Most students should be able to calculate length of the hypotenuse in a right angled triangle. Some students should be able to calculate the length of the hypotenuse in an isosceles triangle when given it

base and perpendicular height.Keywords: Pythagoras, Theorem, Pythagoras, Perpendicular, Right-angled triangle

Learning Activities

Starter/Introduction

Explain that there is a relationship between the three sides of a right angled triangle, which we

will investigate. The start of the lesson is used to discover Pythagoras Theorem by construction.

It is important to note this demonstration is not a proof of the theorem. Using cm squared

paper students draw a 3cm vertical and 4cm horizontal line, the ends of which are joined to

create a right angled triangle. Define the line opposite the right angle as the Hypotenuse side

and have the class measure its length.

At this point the class could predict patterns given the lengths of the three sides are 3cm, 4cm

and 5cm. Construct another right angled triangle to test the hypothesis. When the class

identify the relationship between the three sides is not obvious from the lengths, encourage

them to consider the areas of the shapes draw in proportion to the lengths of each edge using

their previously drawn triangles.

Once the class recognise the pattern is, the sum of the area of the two small squares is equal to

the area of the shape on the hypotenuse side, it may be worthwhile testing this further using the

interactive Geogebra and Autograph V3.3 files in additional resources.

Development

Use the third slide to have the class formally derive Pythagoras Theorem by defining the two

smaller edges as a and b with the hypotenuse as c. Use the interactive Microsoft Excel file towork through a few examples. Students should then be able to work through the problems on

the fourth slide independently.

Plenary

The plenary is intended to provide a real life application for Pythagoras Theorem. Have the

class create a sketch to model the problem as a right angled triangle. Using the sketch, the

class should identify the hypotenuse side as the length of the ladder. Have solutions presented

on mini-whiteboards for assessment and feedback.

Resources:

Mini-Whiteboa

Pythagoras Pro

Interactive

Geogebra &

Autograph V3.File

Interactive

Microsoft Excel

Differentiation

More able:

Students could consider calculating the length between two coordinate pairs using Pythagoras Theorem

Students could formally prove the theorem. See YouTube video for demonstration.Less Able

Students may need additional practise identifying the hypotenuse side. Use Pythagorean triples to simplify calculations.

http://www.youtube.com/watch?v=rb6i4LCoJVshttp://www.youtube.com/watch?v=rb6i4LCoJVs