# Important concepts of pythagorean theorem

#### mathmari

##### Well-known member
MHB Site Helper
Hey!! I am looking at the following question:

Which are the most important concepts that are included at the pythagorean theorem and how can we convince the students for their importance?

Are the concepts meant to be right angled triangle, hypotenuse, etc? Or what are the most important concepts?

For the importance, do we have to say the use of the pythagorean theorem?

If we know the lengths of two sides of a right angled triangle, we can find the length of the third side. #### Klaas van Aarsen

##### MHB Seeker
Staff member
Hey mathmari !!

Right angled triangles play an important role in geometry.
Seeing how we can calculate the hypotenuse from the 2 other sides seems almost magical to me.
It should appeal to students...

Anyway, it was only after high school that I learned how the Pythagorean theorem is used in practice.
It is used to make a right angle!
That is, if you're for instance building a house, you want your walls to be perpendicular to each other.
Much easier to put your furniture in the corners. And less risk of leakage if the roof wouldn't quite fit.
We can take a rope and measure lengths of 3, 4, and 5 meters along it, and put it in a triangle shape.
That triangle shape has a right angle, so now we can build our walls along the rope, and be sure they make a nice right angle.