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 90
^{0}.

- 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 90
^{0}. - o Hypotenuse of any triangle having right angle (90
^{0}) 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?