1. MJ2A Ch 9.1 – Square & Square Roots

2. Bellwork • Solve 1 x 1 6 x 6 11 x 11 2 x 2 7 x 7 12 x 12 3 x 3 8 x 8 4 x 4 9 x 9 5 x 5 10 x 10

3. Assignment Review • Text p. 576 #9 – 18

4. Before we begin… • Please take out your notebook and get ready to work… • Today we will look at perfect squares and square roots…

5. Objective • Students will find the square roots of perfect squares

6. Perfect Squares • A perfect square is the result when 2 of the same numbers are multiplied. • For example, as demonstrated in the bellwork when you multiply 6 x 6 you get 36. • 36 is considered a perfect square. • Any two of the same number can be multiplied and get a perfect square

7. Square roots • The opposite of squaring a number is to find the square root of a number. • A square root is one of the two equal factors of the number • In the previous example the square root of 36 is 6 (which is one of the two equal factors)

8. Square Roots • Additionally, -6 is also a square root of 36. • That is because -6 x -6 = + 36 • Therefore, the square root of 36 is +6 and -6 • Often, the square root of a positive number is noted with the plus/minus symbol (±) • Also, every positive number has a positive and negative square root

9. Special Symbols • The radical sign (√ ) is used to indicate a positive square root. • The symbol (- √ ) is used to indicate the negative square root • Let’s look at an example of a negative square root

10. Example • Find - √121 - √121 indicates the negative square root of 121 Since (-11)(-11) = 121, - √121 = -11 Note: In this instance there is no positive square root!

11. Your Turn • In the notes section of your notebook write the problem and find the square root 1. √49 2. - √ 225 3. - √ 0.16

12. Square Roots & Fractions • To get the square root of a fraction you square root the numerator and the denominator • Example – demonstrate on board using the fraction 9 25

13. Solving Equations • You can solve equations by using square roots. • Remember to square root both sides of the equation • Example – Demonstrate on board using t2 = 25 36

14. Your Turn • In the notes section of your notebook write the problems and solve using square roots • y2 = 4 25 • 196 = a2 • M2 = 0.09

15. Summary • In the notes section of your notebook summarize the key concepts covered in today’s lesson • Today we discussed • Perfect squares • Square roots • Square roots and fractions • Solving problems using square roots

16. Assignment • Text p. 439 #12 - 31 • Reminder • This assignment is due tomorrow • I do not accept answers only. • Make sure that you write the problem and your solution.