A PRESNTATION ON
GOLDEN RATIO
Michael Mastlin
A LITTLE MORE
In any right triangle, the square of the length of the
hypotenuse is equal to the sum of the squares of the
lengths of the legs."
This relationship can be stated as:
and is known as the
 Pythagorean Theorem 
a, b are legs.
c is the hypotenuse
Starting with a right triangle and squares on each side, the middle size square is
cut into congruent quadrilaterals .Then the quadrilaterals are hinged and rotated
and shifted to the big square. Finally the smallest square is translated to cover the
remaining middle part of the biggest square. A perfect fit! Thus the sum of the
squares on the smaller two sides equals the square on the biggest side.
Afterward, the small square is translated back and the four quadrilaterals are directly
translated back to their original position.
Animated Proof of the Pythagorean Theorem
ANIMATED PROOF OF THE PYTHAGOREAN THEOREM
iven:- ABC is a right angle Triangle.
angle B =900
T.P:- AC2
= AB2
+BC2
Construction:- To draw BD ⊥ AC .
A
B C
D
Proof:- In ADB and ABC
Angle A = Angle A (common)
Angle ADB = Angle ABC (each 900
)
ADB ~ ABC ( A.A corollary )
So that AD/AB = AB/AC
AB2
= AD X AC _________(1)
Similarly BC2
= DCXAC _________(2)
Adding (1) & (2) , we get
AB2
+BC2
= AD X AC + DCXAC
= AC (AD +DC)
= AC . AC
=AC2
Therefore
AB2
+BC2
=AC2
PYTHAGOREAN THEOREM IN TEXT BOOK OF 10TH
CLASS
Typical
ExamplEs
ExamplE 1. Find thE lEngth oF aC.
Hypotenuse
AC2
= 122
+ 162
(Pythagoras’ Theorem)
AC2
= 144 + 256
AC2
= 400
AC = 20
A
CB
16
12
Solution :
ExamplE 2. Find thE lEngth oF diagonal d .
10
24 d
Solution:
d2
= 102
+ 242
(Pythagoras 'Theorem)
d = +
=
=
10 24
26
2 2
676
16km
12km
1.A car travels 16 km from east to west. Then
it turns left and travels a further 12 km. Find
the displacement between the starting point
and the destination point of the car.
N
?
Application of Pythagoras’ Theorem
16 km
12 km
A
B
C
Solution :
In the figure,
AB = 16km
BC = 12km
AC2
= AB2
+ BC2
(Pythagoras’ Theorem)
AC2
= 162
+ 122
AC2
= 400
AC = 20km
The displacement between the starting point and the
destination point of the car is 20 km.
Q.) The height of a tree is 5 m. The
distance between the top of it and the tip
of its shadow is 13 m. Find the length of
the shadow L.
Solution:
132
= 52
+ L2
(Pythagoras’ Theorem)
L2
= 132
- 52
L2
= 144
L = 12
5 m
13 m
L
All efforts by yash agarwal

Yash's pythogoras theorem ppt.Class X

  • 1.
  • 2.
  • 6.
    A LITTLE MORE Inany right triangle, the square of the length of the hypotenuse is equal to the sum of the squares of the lengths of the legs." This relationship can be stated as: and is known as the  Pythagorean Theorem  a, b are legs. c is the hypotenuse
  • 7.
    Starting with aright triangle and squares on each side, the middle size square is cut into congruent quadrilaterals .Then the quadrilaterals are hinged and rotated and shifted to the big square. Finally the smallest square is translated to cover the remaining middle part of the biggest square. A perfect fit! Thus the sum of the squares on the smaller two sides equals the square on the biggest side. Afterward, the small square is translated back and the four quadrilaterals are directly translated back to their original position. Animated Proof of the Pythagorean Theorem
  • 8.
    ANIMATED PROOF OFTHE PYTHAGOREAN THEOREM
  • 9.
    iven:- ABC isa right angle Triangle. angle B =900 T.P:- AC2 = AB2 +BC2 Construction:- To draw BD ⊥ AC . A B C D Proof:- In ADB and ABC Angle A = Angle A (common) Angle ADB = Angle ABC (each 900 ) ADB ~ ABC ( A.A corollary ) So that AD/AB = AB/AC AB2 = AD X AC _________(1) Similarly BC2 = DCXAC _________(2) Adding (1) & (2) , we get AB2 +BC2 = AD X AC + DCXAC = AC (AD +DC) = AC . AC =AC2 Therefore AB2 +BC2 =AC2 PYTHAGOREAN THEOREM IN TEXT BOOK OF 10TH CLASS
  • 10.
  • 11.
    ExamplE 1. FindthE lEngth oF aC. Hypotenuse AC2 = 122 + 162 (Pythagoras’ Theorem) AC2 = 144 + 256 AC2 = 400 AC = 20 A CB 16 12 Solution :
  • 12.
    ExamplE 2. FindthE lEngth oF diagonal d . 10 24 d Solution: d2 = 102 + 242 (Pythagoras 'Theorem) d = + = = 10 24 26 2 2 676
  • 13.
    16km 12km 1.A car travels16 km from east to west. Then it turns left and travels a further 12 km. Find the displacement between the starting point and the destination point of the car. N ? Application of Pythagoras’ Theorem
  • 14.
    16 km 12 km A B C Solution: In the figure, AB = 16km BC = 12km AC2 = AB2 + BC2 (Pythagoras’ Theorem) AC2 = 162 + 122 AC2 = 400 AC = 20km The displacement between the starting point and the destination point of the car is 20 km.
  • 15.
    Q.) The heightof a tree is 5 m. The distance between the top of it and the tip of its shadow is 13 m. Find the length of the shadow L. Solution: 132 = 52 + L2 (Pythagoras’ Theorem) L2 = 132 - 52 L2 = 144 L = 12 5 m 13 m L
  • 17.
    All efforts byyash agarwal