1. Lesson 2.4 Math By. Juran Seo p.70~73

2. Lesson 2.4 Math The Signs +, + + +, - - -, - + -, + - ※※I※※If the sign ‘-’ is even number, the answer sign is ‘+’. And if it is odd number, the answer sign is ‘-’. ※ If the signs are different, the answers are negative and if the signs are the same, the answers are positive. p.70~73

3. Lesson 2.4 Math How to multiply Integers :1-The product of two integers with the same sign is positive(greater than 0). EEx) 4·2 = 8 / -3·(-7) = 21 :2-The product of two integers with different signs is negative(less than 0). EEx) 4·(-2) = -8 / -3·7 = -21 p.70

4. Lesson 2.4 Math Q) A diver is exploring a coral reef. The diver’s depth is changing by -6 feet per second. If the diver started at sea level, what is the diver’s position after 10 seconds? A) Have to use the distance formula d=rt d = rt Write the distance formula. d = -6(10) Substitute -6 for r and 10 for t. d = -60 Different signs, so product is negative. p.70

5. Lesson 2.4 Math Multiplication Property of Zero The product of an integer and 0 is 0. Numbers) -4·0=0 Algebra) Any value of a, a·0=0   Identify Property of Multiplication   The product of an integer and 1 is the integer.   Numbers) 4(1) = 4   Algebra) For any value of a, a(1) = a p.71

6. Lesson 2.4 Math -1(6) = -6 Different signs, so product is negative. -8(-2) = 16 Same sign, so product is positive. -15(0) = 0 Product of an integer and 0 is 0. 4(-10)(-12) = -40(-12) = 480 Multiply from left to right. ｜｜ -2 ｜ ·5 = 2 × 5 = 10 -- 2(5)(-6) = (-10) × (-6) = 60 p.71~72 Absolute Value

7. Lesson 2.4 Math