1. 9-1 Square Roots and the Pythagorean Theorem The square of 7 is 7 2 = 49 Also,( -7) 2 =49 The reverse of the square of a number is the square root of a number. The square root of a number is one of its equal factors. The square of 7 is 7 2 = 49 Also,( -7) 2 =49 The reverse of the square of a number is the square root of a number. The square root of a number is one of its equal factors.

2.  All positive real #’s have 2 sq. roots. The positive sq.root is called the principal root, and the other is the negative sq. root.  Sq. roots are written with the radical symbol.  The # inside is called the radicand.   (read plus or minus) is used to write both sq. roots of a positive #.  Perfect squares- #’s whose sq. roots are integers.  Irrational #’s- sq. roots of #’s that aren’t perfect.  All positive real #’s have 2 sq. roots. The positive sq.root is called the principal root, and the other is the negative sq. root.  Sq. roots are written with the radical symbol.  The # inside is called the radicand.   (read plus or minus) is used to write both sq. roots of a positive #.  Perfect squares- #’s whose sq. roots are integers.  Irrational #’s- sq. roots of #’s that aren’t perfect.

3.  positive sq. root  neg. sq. root  zero only has 1 sq. root  is undefined Neg. #’s have no sq. root  positive sq. root  neg. sq. root  zero only has 1 sq. root  is undefined Neg. #’s have no sq. root

4. Examples

5. Completing work for  Calculate b 2  Calculate 4  a  c  Subtract  Do square root  Calculate b 2  Calculate 4  a  c  Subtract  Do square root

6. Examples 1)a=3 b= 4 c=1 2)a=3 b=-2 c=-5 1)a=3 b= 4 c=1 2)a=3 b=-2 c=-5

7. Assignment