1. Algebra 1 Section 2.5 Multiply real numbers Recall: 4 x (-3) means (-3)+(-3)+(-3)+(-3) = -12 Also (-4)(-3) = 12 because – (-12) = 12 Rules for multiplying real numbers 1.The product of two numbers with the same sign is positive. 2.The product of two numbers with opposite signs is negative.

2. Simplify (-8)(-5) (6)(-4) (-11)(3) (-⅔)(-9) (-4)(-3)(2)(-5)

3. If there are an odd number of negative factors, the product is negative. Simplify (-3)(-x) 5(-n)(-n)(-n) (-1)(-a) 2 - (-2) 5

4. Evaluate -8x if x = -3 3x 2 – 5x if x = -4 -2 | x – 5 | if x = -5 Use a calculator. (-18.7)(4.6)(-3.6)

5. Properties of multiplication Commutative property a x b = Associative property (a x b) x c = Identity property a (1) = Identify the property shown. 5(3x7) = (5x3)x7 1 (4) = 4 5(7) = (7)5 b x a a x (b x c) a

6. Page 95 example 4

7. assignment Page 96 Problems 16 – 56 even, 61,62,63