1. The Pythagorean Theorem
Chapter 9.1
Part 2

2. The Converse of the Pythagorean Theorem:
In a triangle with sides a, b, and c; if ,
then the triangle is a right triangle.
Are the following right triangles?
1. a = 9, b = 12, c = 15
2. a = 1, b = 2, c = 3
False.
Not a right triangle.
True. Yes it is a right triangle.

3. In your Notebooks: Is this a right triangle? SHOW YOUR WORK!
4, 5, ) 8, 15, 17
3) 20, 21, ) 3, 8, 15
We will continue taking notes in 5-10 minutes.

4. Word Problems:
Suppose that you drive 4 miles south and then 10 miles east. How far are you away from your starting point?
Step 1: Draw a picture:
4 miles
10 miles

5. Word Problems:
Suppose that you drive 4 miles south and then 10 miles east. How far are you away from your starting point?
Step 2: Set up and equation, and solve.
Distance from starting point
4 miles
10 miles
miles

6. Applications of the Pythagorean Theorem: Use your own paper.
You may work in groups of 2-3.
Passing the AIMS: pg 253, 1-4 all
Create your own word problem using distances, and solve using the Pythagorean theorem.
For example: Bob walked 6 miles north, turned and walked 8 miles west. How far away is he from his original position?
Keep your papers

7. Pythagorean Triples: All three sides of a right triangle are positive integers.
Which of the following are Pythagorean triples. Justify your answers (use converse of Pythagorean Theorem.)
30 , 40 , ) 14, 48, 50
3) 12, 35, ) 48, 55, 73
5) 36, 77, ) 16, 30, 34
7) 9, 40, ) 11, 60, 61

8. Hint: look for GCF and Factor
9) What do the following triples have in common? 10) Which ones are the sides of a right triangle?
3, 4, 5
6, 8, 10
9, 12, 15
12, 16, 20
15, 20, 25
30, 40, 50
Hint: look for GCF and Factor

9. Homework: pg 417 (18, 21-32 all, 37) SHOW YOUR WORK!
For Converse of Pythagorean Theorem: EXPLAIN YOUR ANSWERS
SHOW YOUR WORK!