Course 1 11-4 Adding Integers Learn to add integers.

Adding Integers on a Number Line Course 1 11-4 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.

Adding Integers 11-4 Writing Math Course 1 11-4 Adding Integers Parentheses are used to separate addition, subtraction, multiplication, and division signs from negative integers. –2 + (–5) = –7 Writing Math

Additional Example 1: Writing Integer Addition Course 1 11-4 Adding Integers 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.

Additional Example 1: Writing Integer Addition Course 1 11-4 Adding Integers 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.

Adding Integers 11-4 Check It Out: Example 1 Course 1 11-4 Adding Integers 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.

Adding Integers 11-4 Check It Out: Example 1 Course 1 11-4 Adding Integers 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.

Additional Example 2A: Adding Integers Course 1 11-4 Adding Integers Additional Example 2A: Adding Integers Find the sum. –3 + (–2) Think: + (–2) –3 –6 –5 –4 –3 –2 –1 0 1 –3 + (–2) = –5

Additional Example 2B: Adding Integers Course 1 11-4 Adding Integers 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

Adding Integers 11-4 Check It Out: Example 2A Find the sum. –2 + (–4) Course 1 11-4 Adding Integers Check It Out: Example 2A Find the sum. –2 + (–4) Think: –2 + (–4) –6 –5 –4 –3 –2 –1 0 1 –2 + (–4) = –6

Adding Integers 11-4 Check It Out: Example 2B Find the sum. 3 + (–6) Course 1 11-4 Adding Integers 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

Additional Example 3: Evaluating Integer Expressions Course 1 11-4 Adding Integers 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.

Adding Integers 11-4 Check It Out: Example 3 Course 1 11-4 Adding Integers Check It Out: Example 3 Evaluate z + (–4) for z = 2. z + (–4) Write the expression. 2 + (–4) Substitute 2 for z. –2 Add.

Additional Example 4: Application Course 1 11-4 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. –12 + 35 23 The plane is 23 m above the sea.

Adding Integers 11-4 Check It Out: Example 4 Course 1 11-4 Adding Integers 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 ship. –33 + 54 21 The plane is 21 m above the sea.