PYTHAGOREAN THEOREAM

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PYTHAGOREAN THEOREAM

• http://www.youtube.com/watch?v=uaj0XcLtN5c

http://www.youtube.com/watch?feature=player_detailpage&v=DRRVu-RHQWE

What is the relationship among the lengths of the sides of a right triangle

http://www.youtube.com/watch?v=uaj0XcLtN5c

Calculating this becomes:

9 + 16 = 25

WIKIPEDIACCSC Alignnment: 8.G.B.6

Pythagoras applied to similar triangles

Pythagoras by pentagons

Trig Functions

One of the best known mathematical formulas is Pythagorean Theorem, which provides us with the relationship between the sides in a right triangle. A right triangle consists of two legs and a hypotenuse. The two legs meet at a 90° angle and the hypotenuse is the longest side of the right triangle and is the side opposite the right angle.

Write it down as an equation:

abc triangle a^2 + b^2 = c^2

The Pythagorean Theorem tells us the relationship in every right triangle

a^2+b^2=c^2

Example:

Example: Does this triangle have a Right

Angle?

10 24 26 triangle

Does a^2 + b^2 = c^2 ?

C^2 = 10^2+24^2 = 676

They are equal, so ...

Yes, it does have a Right Angle!

Let's check if the areas are the same:

3^2 + 4^2 = 5^2

Calculating this becomes:

9 + 16 = 25

It works ... like Magic!

• Example: Solve this triangle.• A^2 + b^2 = c^2

• 5^2 + 12^2 = c^2• 25 + 144 = c2• 169 = c2• C^2 = 169• c = √169• c = 13

example: Does this triangle have a Right Angle?• Triangle with roots

3 + 5 = 8 ? Yes, it does!So this is a right-angled triangle

(√3)^2 + (√5)^2 = (√8)^2 ?

Leg^2 + leg^2 = hypotenuse ^2

You Can Prove The Theorem Yourself !

proof of the Pythagorean Theorem and it converse: In any right triangle, the sum of the squares of the legs equals the square of the hypotenuse (leg2 + leg2 = hypotenuse2). The figure below shows the parts of a right triangle.

Leg^2 + leg^2 = hypotenuse^2

hypotenuse2 – leg2 = leg2

proof• 3^2 + 4^2 = x^2

26^2 – 24^2 =x^2 • 9 + 16 = x^2

676 – 576=x^2• √25 = √x^2

√100 = √x^2

10 = x • √25 = x • 5 = x

distance formula: The distance d between the points A = (x1, y1) and B = (x2, y2) is given by the formula:

The distance formula can be obtained by creating a triangle and using the Pythagorean Theorem to find the length of the hypotenuse. The hypotenuse of

the triangle will be the distance between the two points.

distance formula

For example, consider the two points A (1,4) and B (4,0),

so: x1 = 1, y1 = 4, x2 = 4, and y2 = 0.

Substituting into the distance formula we have:

Sides relationships

PRACTICAL APPLICATION

SOH, CAH, TOA

The Pythagorean theorem

Right Angle Trignometry

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