HYPOTENUSE OF RIGHT ANGLED TRIANGLE

Students` Learning Outcomes

• Define hypotenuse of right angled triangle.

Information for Teachers

• Closed figure consisting of three sides is called triangle.
• The longest side of the triangle is called the “hypotenuse” of a triangle.
• Right angle is an angle which is of 90⁰.
  

• In right angled triangles the side opposite to right angle is called hypotenuse (BC).

Material / Resources

Writing board, chalk / marker, duster, geometry box, chart, ruler, cutter, textbook

Introduction

• Draw a right angled triangle on the board and name the three sides of triangle as written above.
  

 

• Ask students following questions:

 

o   What is triangle?

o   What is a right angled triangle?

o   Can you observe which side of the triangle is the longest?

o   Which side of the right angled triangle is longest?

• Tell the students that today we will learn about hypotenuse of right angled triangle.

Development

Activity 1

• Trace the right angled triangle on the chart and cut the following shapes to make the students better understand about the hypotenuse.
• Call a student and ask him to measure the three sides of triangle.
  

 

• 
  
• Write measurements of sides on the board.
• Ask the students to tell which side is largest?
• Now draw the square along sides of triangle and then tell them the side AB is the hypotenuse of triangle ABC.
• Tell them the longest side of right angle triangle is called hypotenuse.
• The longest side is opposite to right angle.
• So in right angle triangle the side opposite to right angle is longest and called hypotenuse.
• ‘A’ and ‘B’ are the other two sides of triangle.

 

Activity 2

• Draw the “Rectangle ABCD” on the board and also draw diagonal AC
• Ask the student that how many triangle are there? (Two)
• Are they right angled triangles? (Yes)
  

 

• Ask them which AB, BC, CA, AD and AC are longest? (AC is the longest)
  

 

 

• Ask them is AC opposite to right angles, angle D and angle B (Yes)
• Ask them what is the longest side of right angle triangle? (Hypotenuse)
• Write hypotenuse along AC

 

Sum up / Conclusion

• Recall the definition and process of finding hypotenuse.
  

 

• o   From the three sides of right angled triangle, longest side is called the hypotenuse.
• o   Right angled is an angle which is of 90⁰.
• o   Hypotenuse of any triangle having right angle (90⁰) is called hypotenuse of right angled triangle.

 

Assessment

• Draw a Rectangle PQRS and ask the students names of right angled triangles shown in the figure.
• Ask which is the longest?
• Ask what longest side is called?
  

 

• Draw a right angle triangle and ask students to draw the same on their copies.
  

 

 

• Make a table and ask the students to tick hypotenuse of triangle XYZ.
  

 

 

• Take a round of the class and check the answer of each student.

 

Follow up

• Assign following types of questions as homework to assess how much students learned regarding the topic.
• Please indicate which is the hypotenuse of both right angled triangle ABC given below;
  

 

• ABC and PQR are two right angled triangles. Please measure hypotenuse of both triangles and tell hypotenuse of which triangle is how much longer?