11.2 Pythagorean Theorem

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Chapter 11, Section 2: Pythagorean Theorem

Transcript of 11.2 Pythagorean Theorem

Warm Up:

What is the sign of the product of two negative numbers?

Find the Product or Sum:(-2)² =(-6)² =6² + 9² = 4² + 10² =

The Pythagorean Theorem

Chapter 11, Section 2

Parts of Right TrianglesThe sides on either side of the right angle (90º) are

called the LEGS

The side adjacent to the right angle is called the HYPOTENUSE.

The HYPOTENUSE of a Right Triangle Is always LONGER then the

LEGS.

Pythagorean Theorem

Use Pythagorean Theorem to determine any missing lengths of a RIGHT Triangle.

A² + B² = C²

A and B are lengths of the LEGS.C is the length of the HYPOTENUSE.

Another way: C = √A² + B²

Determine the Length of the Hypotenuse

C² = A² + B²

C² = 6² + 8²

C² = 36 + 64

C = √100

C = 10

8 cm

6 cm

C cm

Right Angle

The legs are A and B for Pythagorean.A = 6 cm, B = 8 cm

Try These: Find the Missing Side Length of each Triangle

Triangle 1: Legs: 3ft and 4ft

Triangle 2: Leg: 12m; Hypotenuse: 15m

Find the value of X

A² + B² = C²

6² + x² = 9²36 + x² = 81

X² = 45X = √45

√45 = 6.7 (rounded)

9 in.

6 in.X in.

Use the Square Root Table to Approximate Square Roots

In your book, page 746 has a whole table of square root solutions.

Find the number in the N column, then find the answer in the √N column.

Or use a calculator, just remember to round.

Identifying Right TrianglesTo see if a triangle IS a right triangle, plug the

measurements into the Theorem.

Sides: 12m, 15m, and 20m.Is this triangle a Right Triangle?

A² + B² = C², 12² + 15² = 20² ?

144 + 225 = ? 400

369 ≠ 400

The triangle with these measurements is NOT a right triangle.

Right ▲ or Not?

Triangle 1: 7in, 8in, 9in?

Triangle 2: 3m, 4m, 5m?

Triangle 3: 5mm, 6mm, 10mm?

Assignment #31

Pages 567-568: 10-32 all.