1. Pythagorean Theorem and Right Triangles Mrs. Spanier Pre-Algebra

2. Discuss with a neighbor… 1. What is Pythagorean Theorem used for? 2. What is the formula?

3. Please Do Now… Fill in the blanks on the Pythagorean Theorem GO. Do this on your own. Now check with a neighbor.

4. What is Pythagorean Theorem? a² + b² = c² a b c Video

5. Is this a right triangle? a² + b² = c² 12² + 35² = 37² 144 + 1225 = 1369 1369 = 1369 So… YES! 12 35 37

6. Is this a right triangle? a² + b² = c² 10² + 25² = 26² 100 + 625 = 676 725 = 676 So… NO! A = 10 B = 25 C = 26

7. Is this a right triangle? a² + b² = c² 12² + 30² = 32² 144 + 900 = 1024 1044 = 1024 So… NO! A = 12 B = 30 C = 32

8. Find the missing side: a² + b² = c² 6² + 8² = c² 36 + 64 = c² 100 = c² 10 = c 6 8 c√√

9. Example on GO – Find the missing side: a² + b² = c² 15² + b² = 39² 225 + b² = 1521 b² = 1296 b = 36 A = 15 B = ? C = 39√√ Now try the other 2 on your GO…

10. Find the missing side: 7² + b² = 11² 49 + b² = 121 b² = 72 b = about 8.5 A = 7 B = ? C = 11√√

11. Find the missing side: a² + b² = c² a² + 12² = 15² a² + 144 = 225 a² = 81 9 = c A = ? B = 12 C = 15√√

12. Find the missing side: a² + 24² = 30² a² + 576 = 900 a² = 324 a = 18 a 24 30√ √

13. You need a pencil and scratch paper…

14. Choose your answers! 50 75 12.7 17.3 7.28 2.23 no7.42 16.16 yes 0.9 8.56 12 10.9 9.4 24 14.4 5.74 20.6 26.5 12.4

15. Tell someone… How do you know whether to add or subtract when solving with Pythagorean theorem?

16. You try: Find the length of each cable in the figure below. 45 m

17. Quiz Time! http://www.funtrivia.com/playquiz/quiz20 49161776b68.html http://www.funtrivia.com/playquiz/quiz20 49161776b68.html http://www.funtrivia.com/playquiz/quiz20 49161776b68.html http://www.funtrivia.com/playquiz/quiz20 49161776b68.html