1. and Squares Square Roots

2. If a square measures 4 inches on each side, how would you find its area? 4 inches

3. Remember how to calculate the area? 4 inches A = L X W A = 4 in. 4 in. 4 inches A = 16 in. 2

4. A square must have the same length and width. 4 inches A = 4 in. 4 in. 4 inches A = L x W

5. To square a number means to multiply it by itself. 4 squared means 4 x 4 Take the number 4 And square it!

6. There is a shorter way to write 4 x 4. Say: “4 squared” or “4 to the 2 nd power”.

7. This is another formula for finding the area of a square. Same or Side s A = s 2 s is the side length

8. Opposites Squares and Square Roots are opposites of each other. JUST LIKE>> Adding and Subtracting are opposites of each other. Multiplying and Dividing are opposites of each other.

9. The symbol used to indicate a root is the radical symbol

10. Every radical expression has three parts… Index Radicand Radical

11. The index of a square root is always 2.

12. but, it is normally written as The square root of 49 could be written as

13. What does square root mean?

14. The square root of a number is a number that, when multiplied by itself, gives back the original or same number.

15. What is a square root? the measure of the side of the square 25 = 5 ?

16. What is the square root of 36? 36 =6

17. because Also, because EXAMPLES: Every square root has two answers. ±7

18. Your Turn: Give Both Answers 1. √81 2. √121 3. √36

19. Square Roots with a Negative on the outside –√ 49 = –7 –√ 100 = –10 –√ 225 = –15

20. Your Turn 1. –√ 25 2. –√144 3. –√121

21. You may not have a negative number inside the square root. It is undefined. (√-9)

22. These numbers are called perfect squares

23. If a number is a perfect square, then you can find its exact square root. A perfect square is simply a number that can be written as the square of WHOLE number.

24. What are the first 10 whole numbers that are perfect squares? 1, 4, 9, 16, 25, 36, 49, 64, 81, 100

25. Now, write 11²- 25²in your notebook. You will have a quiz on these. STUDY THEM: rewrite in your notebook, make flash cards, make your own quiz, etc.

26. 11² = 121 18² = 324 12² = 144 19² = 361 13² = 169 20² = 400 14² = 196 21² = 441 15²= 225 22² = 484 16² = 256 23² = 529 17² = 289 24² = 576 25² = 625