Name the integer that corresponds to each point. Warm Up Add. 1. 2 + 3 2. 7 + 4 3. 8 + 5 4. 17 + 12 Name the integer that corresponds to each point. 5. A 6. B 5 11 13 29 –3 5 1

Problem of the Day Karen earned 40 points on part I of a test, 26 points on part II, and 25 points on part III. What number of points did Karen earn on parts I and III combined? 65 2

Sunshine State Standards Preview of MA.7.A.3.1 Use and justify the rules for adding…integers. Preview of MA.7.A.3.2 Add…integers,…including solving problems in everyday contexts.

Adding Integers on a Number Line Move right on a number line to add a positive integer. Move left on a number line to add a negative integer. Adding Integers on a Number Line 4

Parentheses are used to separate addition, subtraction, multiplication, and division signs from negative integers. –2 + (–5) = –7 Writing Math 5

Additional Example 1: Writing Integer Addition Write the addition modeled on each number line. A. B. + (–4) 5 –1 0 1 2 3 4 5 6 The addition modeled is 5 + (–4) = 1. +7 (–4) –5 –4 –3 –2 –1 0 1 2 3 4 The addition modeled is –4 + 7 = 3. 6

Additional Example 1: Writing Integer Addition Write the addition modeled on each number line. C. + (–5) 3 –4 –3 –2 –1 0 1 2 3 4 The addition modeled is 3 + (–5) = –2. 7

Write the addition modeled on each number line. A. Check It Out: Example 1 Write the addition modeled on each number line. A. B. + (–3) 6 –1 0 1 2 3 4 5 6 The addition modeled is 6 + (–3) = 3. +3 (–2) –5 –4 –3 –2 –1 0 1 2 3 4 The addition modeled is –2 + 3 = 1. 8

Write the addition modeled on each number line. Check It Out: Example 1 Write the addition modeled on each number line. C. + (–7) 4 –4 –3 –2 –1 0 1 2 3 4 The addition modeled is 4 + (–7) = –3. 9

Additional Example 2A: Adding Integers Find the sum. –3 + (–2) Think: + (–2) –3 –6 –5 –4 –3 –2 –1 0 1 –3 + (–2) = –5 10

Additional Example 2B: Adding Integers Find the sum. 6 + (–8) Think: +(–8) 6 –3 –2 –1 0 1 2 3 4 5 6 7 6 + (–8) = –2 11

Check It Out: Example 2A Find the sum. –2 + (–4) Think: –2 + (–4) –6 –5 –4 –3 –2 –1 0 1 –2 + (–4) = –6 12

Check It Out: Example 2B Find the sum. 3 + (–6) Think: + (–6) 3 –3 –2 –1 0 1 2 3 4 5 6 7 3 + (–6) = –3 13

Additional Example 3: Evaluating Integer Expressions Evaluate y + (–2) for y = 7. y + (–2) Write the expression. 7 + (–2) Substitute 7 for y. 5 Add. 14

Check It Out: Example 3 Evaluate z + (–4) for z = 2. z + (–4) Write the expression. 2 + (–4) Substitute 2 for z. –2 Add. 15

Additional Example 4: Application A sunken ship is 12 m below the sea level. A search plane flies 35 m above the sunken ship. How far above the sea is the plane? The ship is 12 m below the sea level and the plane is 35 m above the ship. –12 + 35 23 The plane is 23 m above the sea. 16

The plane is 21 m above the sea. Check It Out: Example 4 A sunken treasure chest is 33 m below the sea level. A search plane flies 54 m above the sunken treasure chest. How far above the sea is the plane? The treasure chest is 33 m below the sea level and the plane is 54 m above the treasure chest. –33 + 54 21 The plane is 21 m above the sea. 17