The document describes a lesson on the Pythagorean theorem for 9th grade mathematics. The lesson uses the GeoGebra software and is a team effort between mathematics and IT teachers. Students will be presented with information on Pythagoras and his work. They will then work through example problems applying the Pythagorean theorem and find other examples of rectangular triangles formed by towns in Bulgaria.

4. Lesson Type: Exercise
Requirement to the venue: (Multimedia cabinet)
Aim of the lesson: To present the practical
application of the Pythagorean theorem
Short annotation: Lesson for 9th
grade in
Mathematics on Pythagorean Theorem. The
lesson explores the dynamics of the GeoGebra
software product, thus making students active in
building and shaping new knowledge. The lesson
is team work of two mathematics and IT teachers.

6. А
В
С
С1
b1 a1
a
b
hc
c
cathetes
b
а
→



hypotenuseс →
heightСС →1
Projections of the cathetes
on the hypotenuse
a1
b1

8. Here is a presentation
about the life and
activity of Pythagoras,
prepared as homework
and presented by
Maria Zlatkova and
Valeri Mitov

10. A raw sticks out
from the water at high
0.30 m. If it’s inclines, the
upper end, it reaches the
surface of the water at
1.20 m. how deep is the
water?
Урокът продължава със задачи, които демонстрират
приложението на Питагоровата теорема

12. Distance
The following towns are marked
on the map: Ruse, Shumen and Sliven,
together they form a rectangular triangle.
If we know that the distance between
Ruse and Shumen is 100 km, and this
between Shumen and Ruse is 130km.
How many kilometers is the distance
between Sliven and Ruse?
Solve the problem.
Search for other towns in Bulgaria
that form a rectangular triangle.

15. Find dimensions for the best Cross-section
of beam, which can be made of log with diameter
42 cm. The cross-section have to suits the
following requirements: It has to be rectangle (for
example ABCD), and if we draw high from angles
“A” and “C” to the diagonal BD, they should divide
him on three equal parts.