1. ALGEBRA READINESS LESSON 2-3 Warm Up Lesson 2-3 Warm Up

2. ALGEBRA READINESS LESSON 2-3 Warm Up Lesson 2-3 Warm Up

3. ALGEBRA READINESS “Subtracting Integers” (2-3) How can you use a number line to subtract integers? To subtract numbers using a number line, start at the first number and move / jump the number of units right (+) or left (-) that the second number tells you to.

4. ALGEBRA READINESS Find –3 – 2 using a number line. –3 – 2 = –5 Start at –3. Move left 2 units Subtracting Integers LESSON 2-3 Additional Examples

5. ALGEBRA READINESS “Subtracting Integers” (2-3) What is the rule for subtracting numbers? Rule: Subtracting Numbers: To subtract a number, you can add its opposite (That’s why two negatives equal a positive! - “add the opposite of a negative” = “add a positive” ). Examples: 3 - 5 = 3 + (-5) = -2 3 – (-5) = 3 + 5 = 8

6. ALGEBRA READINESS Find each difference. a. –5 – (–7) b. –9 – 6 –5 – (–7) = –5 + 7 To subtract –7, add its opposite, 7. –5 + 7 = 2The sum has the same sign as 7. –9 – 6 = –9 + (–6) To subtract 6, add its opposite, –6. = –15 The sum of two negative integers is negative. Subtracting Integers LESSON 2-3 Additional Examples

7. ALGEBRA READINESS Simplify each expression. a. –11.6 – (–14) = 2.4 Add. = + Use common denominators ( ) 4949 6969 = Add the numerators. 10 9 = or 1 Write in simplest form. 10 9 1919 10 9 b. – (– ) 2323 4949 = –11.6 + 14 The opposite of –14 is 14. 2323 4949 4949 4949 = + Add “the opposite of” - = +. Subtracting Integers LESSON 2-3 Additional Examples 2 x 3 = 6 3 x 3 = 9

8. ALGEBRA READINESS Juan owes his sister $14. She told him to subtract $8 of what he owes if he feeds the dog. Write an integer to show Juan’s balance if he feeds the dog. Find –14 – (–8). The integer –6 shows that Juan will owe his sister $6. –14 – (–8) = –14 + 8 To subtract –8, add its opposite, 8. = –6The sum has the same sign as –14. Subtracting Integers LESSON 2-3 Additional Examples

9. ALGEBRA READINESS Find each difference. 1.3 – 62.–7 – 83.10 – (–4) 4.–9 – (–9) –3–1514 0 Subtracting Integers LESSON 2-3 Lesson Quiz