2-2 HW = Pg. 75-77 #12-32e, 33-38, 44-50e, 62-78e

2-2 HW Continued

1.) Subtraction can be turned into addition- adding the opposite of the second number is

equivalent to subtracting the number

2.) Rules- a - b = a + (-b)- Ex: 3 - 5 = 3 + (-5) = -2

Terms = parts of an expression that are separated by addition or subtraction signs- Ex: -9-2x has 2 terms,

2-3 Subtraction of Real Numbers

24 7 9 has 3 termsy x

Important Rules to follow with Addition, DO NOT work for subtraction!

• Commutative Property

• Associative Property

• Property of Zero (Inverse Property)

This property STILL works for subtraction• Identity Property

a – 0 = a

5-4 4-5a b b a

( ) ( ) 8-(7-6) (8-7)-6a b c a b c

( ) 0 8-(-8)=8+8=16

a-(-a) = a+a=2a

a a

PracticeUse the subtraction rule to rewrite the

subtraction expression as an equivalent addition expression. Then evaluate the expression.

• 1.) 4-5

• 2.) 3-(-8)

• 3.) 0-7

• 4.) 2-(-3)-6

• 5.) 2 1 1( )

3 6 3

:

1.)4 5 4 ( 5) 1

2.)3 ( 8) 3 ( 8) 11

3.)0 7 0 ( 7) 7

4.)2 ( 3) 2 ( 3) 5

2 1 1 2 1 15.) ( ) ( ) ( )

3 6 3 3 6 34 1 2 5

( )6 6 6 6

Answers

Practice 2Evaluate the expression

1.) 8-11-(-6)2.) 3-(-8)+(-9) 3.) –7+42-63

4.) 6-1+10-(-8) 5.)

Find the terms of the expression

6.) -4-y 7.) -3x+6 8.) x-y-7

Evaluate the function for these values of x: -2, -1, 0, and 1. Organize your results in a table

9.) y = x - 8 10.) y = -x + 12

4 2 5( )

9 3 6

Practice 2 - Answers1.) 8-11-(-6) = 8+(-11)+(+6) = 3

2.) 3-(-8)+(-9) = 3+(+8)+(-9) = 2

3.) –7+42-63= -7+42+(-63) = -28

4.) 6-1+10-(-8) = 6+(-1)+10+(+8) = 23

5.)

6.) -4-y : 2 terms –4 and y

7.) -3x+6 : 2 terms –3x and 6

8.) x-y-7 : 3 terms x, -y and -7

9.) 10.)

4 2 5 8 12 15 -35 17( ) = - ( ) ( ) = 1

9 3 6 18 18 18 18 18

X -2 -1 0 1

Y -10 -9 -8 -7

X -2 -1 0 1

Y 14 13 12 11

When will I ever use

this?

Summary• Adding the ___________ of a number is

equivalent to subtracting the number.

• The following properties DO NOT work for subtraction _______________, _______________, and _______________.

• The ___________ ______________ is the only addition property that works for subtraction.

• The parts in a expression separated by addition symbols are called___________.

Check Yourself

Pg. 82-85 #16-70 eoe, Quiz 1 #1-20 and study for Ch.2 Quiz 1

• # 16-34: find the difference by changing subtraction to addition of the opposite

• #36-50: evaluate the expression by substituting first

• #52-58: find the terms and list them

• #60-70: evaluate the expression