* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download 1 Lesson 69--Negative Numbers/Absolute Value/Adding Signed
Survey
Document related concepts
Foundations of mathematics wikipedia , lookup
Ethnomathematics wikipedia , lookup
Georg Cantor's first set theory article wikipedia , lookup
Positional notation wikipedia , lookup
Infinitesimal wikipedia , lookup
Law of large numbers wikipedia , lookup
Location arithmetic wikipedia , lookup
Hyperreal number wikipedia , lookup
Surreal number wikipedia , lookup
Mathematics of radio engineering wikipedia , lookup
Large numbers wikipedia , lookup
Real number wikipedia , lookup
Division by zero wikipedia , lookup
Transcript
Lesson 69--Negative Numbers/Absolute Value/Adding Signed Numbers Every postive number has an opposite to the left of zero on the number line. 10 9 8 7 6 5 4 3 2 1 0 1 2 3 4 5 6 7 8 9 10 +4 means 4 units to the right of zero -4 means 4 units to the left of zero Numbers that have either a plus or minus sign are called _______________ _________________. Each opposite is the same distance away from zero. What do we call the distance away from zero? Absolute Value-- 1 2 Let's look at adding signed numbers. Ex: (+2) + (3) 5 We can use number lines to help us add signed numbers. 1 2 3 4 1 0 2 3 5 4 Ex: Use arrows and a number line to add (3) and (+5). 5 1 2 3 4 1 0 2 3 5 4 Ex: (+4) + (+2) 5 4 3 2 1 0 1 2 3 4 5 3 2 1 0 1 2 3 4 5 Ex: (1) + (3) 5 4 Now we aren't going to want to sketch a number line every time we add signed numbers. There has to be some rules we can follow. 3 1. To add numbers of the same numbers just add the numbers as usual and carry the sign of the two numbers into your answer. Ex: (2) + (3) = Ex: (-2) + (-3) = 2. To add numbers of opposite signs just subtract the numbers and carry the sign of the number that has the largest absolute value (or use the sign of the number you have "more" of). Ex: (4) + (+3) = Ex: (2) + (+8) = Ex: (45) + (72) = Ex: (25) +(+63) = Ex: (4) + (+3) + (5) + (7) = On Your Own Ex: Use a number line to add the following. b. (-3) + (-4) a. (-2) + (+4) 5 4 3 2 1 0 1 2 3 4 5 10 9 8 7 6 5 4 3 2 1 0 1 2 3 4 5 6 7 8 9 10 Ex: Add. c. (-14) + (+2) d. (41) + (-8) e. (-4) + (-15) 4