9-4 Adding Integers Course 1 Warm Up Warm Up Lesson Presentation Lesson Presentation Problem of the Day Problem of the Day

Warm Up Add Name the integer that corresponds to each point. 5. A6. B 5 11 –3 Course Adding Integers

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 Course Adding Integers

Learn to add integers. Course Adding Integers

Course Adding Integers 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.

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

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

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

Course Adding Integers Try This: Example 1A & 1B Write the addition modeled on each number line. A. B. 6 + (–3) The addition modeled is 6 + (–3) = 3. (–2) +3 The addition modeled is –2 + 3 = 1. – –5 –4 –3 –2 –

Course Adding Integers Try This: Example 1C Write the addition modeled on each number line. C. 4 + (–7) The addition modeled is 4 + (–7) = –3. –4 –3 –2 –

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

Course Adding Integers Additional Example 2B: Adding Integers Find the sum. B. 6 + (–8) 6 + (–8) = –2 +(–8) 6 –3 –2 – Think:

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

Course Adding Integers Try This: Example 2B Find the sum. B. 3 + (–6) 3 + (–6) = –3 + (–6) 3 –3 –2 – Think:

Course Adding Integers Additional Example 3: Evaluating Integer Expressions Evaluate y + (–2) for each value of y. A. y = 7 B. y = 1 y + (–2)Write the expression. 7 + (–2)Substitute 7 for y. 5Add. y + (–2)Write the expression. 1 + (–2)Substitute 1 for y. –1Add.

Course Adding Integers Try This: Example 3 Evaluate z + (–4) for each value of z. A. z = 2 B. z = 3 z + (–4)Write the expression. 2 + (–4)Substitute 2 for z. –2Add. z + (–4)Write the expression. 3 + (–4)Substitute 3 for z. –1Add.

Course Adding Integers 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. – The plane is 23 m above the sea.

Course Adding Integers Try This: Example 4 A sunken ship is 33 m below the sea level. A search plane flies 54 m above the sunken ship. How far above the sea is the plane? The ship is 33 m below the sea level and the plane is 54 m above the ship. – The plane is 21 m above the sea.

Lesson Quiz Find each sum (–3) 2. – –8 + (–4) 4. Evaluate x + 5 for x = –4. 5. At midnight on a winter night, the temperature was –12°F. By 10 A.M. the temperature had risen 42°F. What was the new temperature? –3 4 Insert Lesson Title Here –12 1 Course Adding Integers 30°F