Measurement

Pythagorean Relationship

Who was Pythagoras?

Why all the fuss about somedead Greek guy?

(585 or 565 - 500 B.C.)

It all started with the

Pyramids!

A couple thousand years before

Pythagoras, the Egyptians used a unique method to

make sure the base of each pyramid was

square.

How NOT to build a pyramid…

Measuring a square corner using a …

ROPE??

The Egyptian engineers used a rope tied together at the ends with 12 knots tied in equal distances around the rope.

Measuring a square corner using a …

ROPE??

They knew that when the rope was shaped into a triangle with sides of 3, 4, and 5 it created a right angle between the sides of 3 and 4. 3

4 5

Important term…

In a right angle triangle, the side of

the triangle opposite the right angle is called the

hypotenuse.

hypotenuse

legs

Activity

You will work in pairs…

You will need…• centimetre grid paper• scissors

Concept Development Page 246, Questions 1-2

So…who was Pythagoras?

• Greek – described as the first pure mathemetician

• Lived ~ 2500 years ago…

• Led a secretive society, half scientific and

half religious, that he founded in what is now

southern Italy

Pythagorean relationship

hypotenuse

legs

• In a right triangle, the sum of the

squares (area) of the legs is equal to

the square (area) of the hypotenuse.

Pythagorean relationship

a2 + b2 = c2

a

c

b

bArea =

b2

Area = a2a

c

Area = c2

Assignment

Handout sheet

Page 482, Questions 1,2,4,5,6,7

Pythagorean theorem