Multiplying ~ and ~ Dividing Real  Numbers

KEY CONCEPTS

 1: Identity property of multiplication/division: X(1)=X

Ex: 1(5)= 5   Ex: 1(-5)= -5 

 2: multiplication/division property of 0: X(0)=0

Ex: 35(0)= 0   Ex: -35(0)= 0

  3: multiplication/division property of -1: -1X=-X

Ex: -1(5)= -5   Ex: -1(-5)= 5

 Note- the rules are the same for multiplying and dividing exept for the sign.

Multiply/Divide #'s with same sign: always position

                               Different sign: always negative

                                                                                     Evaluate: -2xy if x=-20,y=-3

 (-2)(-20)(-3)= -120

The inverse property of multiplication:

 reciprocal> a(1/a)=1

Ex: -x/y for x= 3/4, y=-5/2

Solve: (-3/4)/(-5/2)=(-3/4)(-2/5)

Exponents

Simplifying

(x2)(x3)=(xx)(xxx)= (xxxxx)=(x5)

TIME FOR PRACTICE!!!

1. 3(-5)=?

2. -9(-9)=?

3. X=-2  (x5)=?

4. 6/-3=?

5. (-6)(-2)(8)=?